C# 7.1 and .NET Core 2.0 ??? Modern Cross-Platform Development E-Book

Mark J. Price

• Herausgeber: Packt Publishing
• Kategorie: Fachliteratur
• Sprache: Englisch
• Veröffentlichungsjahr: 2017

Seitenzahl: 636

Beschreibung

C# 7.1 and .NET Core 2.0 – Modern Cross-Platform Development, Third Edition, is a practical guide to creating powerful cross-platform applications with C# 7.1 and .NET Core 2.0. It gives readers of any experience level a solid foundation in C# and .NET. The first part of the book runs you through the basics of C#, as well as debugging functions and object-oriented programming, before taking a quick tour through the latest features of C# 7.1 such as default literals, tuples, inferred tuple names, pattern matching, out variables, and more.

After quickly taking you through C# and how .NET works, this book dives into the .NET Standard 2.0 class libraries, covering topics such as packaging and deploying your own libraries, and using common libraries for working with collections, performance, monitoring, serialization, files, databases, and encryption. The final section of the book demonstrates the major types of application that you can build and deploy cross-device and cross-platform. In this section, you'll learn about websites, web applications, web services, Universal Windows Platform (UWP) apps, and mobile apps. By the end of the book, you'll be armed with all the knowledge you need to build modern, cross-platform applications using C# and .NET.

Leseprobe

C# 7.1 and .NET Core 2.0 – Modern Cross-Platform Development

Third Edition

Create powerful applications with .NET Standard 2.0, ASP.NET Core 2.0, and Entity Framework Core 2.0, using Visual Studio 2017 or Visual Studio Code

Mark J. Price

BIRMINGHAM - MUMBAI

C# 7.1 and .NET Core 2.0 – Modern Cross-Platform Development

Third Edition

Copyright © 2017 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

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Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: March 2016

Second edition: March 2017

Third edition: November 2017

Production reference: 1291117

Published by Packt Publishing Ltd.

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ISBN 978-1-78839-807-7

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Credits

Author

Mark J. Price

Copy Editor

Tom Jacob

Reviewers

Dustin Heffron

Efraim Kyriakidis

Proofreader

Safis Editing

Acquisition Editor

Ben Renow-Clarke

Indexer

Rekha Nair

Project Editor

Radhika Atitkar

Graphics

Kirk D'Penha

Content Development Editor

Chris Nelson

Production Coordinator

Shantanu Zagade

Technical Editors

Bhagyashree Rai

Gaurav Gavas

About the Author

Mark J. Price is a Microsoft Certified Solutions Developer (MCSD), Microsoft Specialist: Programming in C#, and Episerver Certified Developer, with more than 20 years of educational and programming experience.

Since 1993, Mark has passed more than 80 Microsoft programming exams, and he specializes in preparing others to pass them too. His students range from professionals with decades of experience to 16-year-old apprentices with none. He successfully guides all of them by combining educational skills with real-world experience in consulting and developing systems for enterprises worldwide.

Between 2001 and 2003, Mark was employed full-time to write official courseware for Microsoft in Redmond, USA. His team wrote the first training courses for C# while it was still an early alpha version. While with Microsoft, he taught "train-the-trainer" classes to get Microsoft Certified Trainers up-to-speed on C# and .NET.

Currently, Mark creates and delivers classroom and e-learning training courses for Episerver's Digital Experience Cloud, the best .NET CMS for Digital Marketing and E-commerce. He is an Episerver Certified Developer (ECD) on Episerver CMS.

In 2010, Mark studied for a Postgraduate Certificate in Education (PGCE). He taught GCSE and A-Level mathematics in two London secondary schools. He holds a Computer Science BSc Hons. degree from the University of Bristol, UK.

Thank you to my parents, Pamela and Ian, for raising me to be polite, hardworking, and curious about the world. Thank you to my sisters, Emily and Juliet, for loving me despite being their awkward older brother. Thank you to my friends and colleagues who inspire me technically and creatively. Lastly, thanks to all the students I have taught over the years for motivating me to be the best teacher that I can be.

About the Reviewers

Dustin Heffron is a software engineer by day and an independent game developer by night. He has over 10 years of experience programming in various languages, eight of which have been in working with C# and .NET. 

Currently, Dustin develops tools to automate and test medical instruments at Becton Dickinson. He is also the cofounder and CEO for SunFlake Studios. Dustin has a long history of reviewing for Packt, including XNA 4.0 Game Development by Example: Beginner's Guide, C# 6 and .NET Core 1.0: Modern Cross-Platform Development, and the video tutorial series XNA 3D Programming by Example. He also coauthored the video tutorial series XNA 3D Toolkit with Larry Louisiana.

I'd like to thank my wife for helping to push me to be the best that I can be, every day.

Efraim Kyriakidis is a skilled software engineer with over 10 years of experience on developing and delivering software solutions for diverse customers and projects. He's well-versed in all stages of the software development life cycle. His first acquaintance with computers and programming was a state of the art Commodore 64, back in the '80s as a kid. Since then he has grown and received his Diploma from Aristotle University Thessaloniki in Greece. Throughout his career, he mainly worked with Microsoft technologies, using C# and .NET since .NET 1.0. He currently works for Siemens AG in Germany as a software developer.

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Table of Contents

Preface

What this book covers

Part 1 – C# 7.1

Part 2 – .NET Core 2.0 and .NET Standard 2.0

Part 3 – App Models

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Downloading the color images of this book

Errata

Piracy

Questions

Hello, C#! Welcome, .NET Core!

Setting up your development environment

Using alternative C# IDEs

Deploying cross-platform

Installing Microsoft Visual Studio 2017

Choosing workloads

Choosing additional components

Installing Microsoft Visual Studio Code

Installing Microsoft Visual Studio Code for macOS

Installing .NET Core SDK for macOS

Installing Node Package Manager for macOS

Installing the Visual Studio Code extension for C#

Installing Visual Studio for Mac

Installing Xcode

Downloading and installing Visual Studio for Mac

Understanding .NET

Understanding .NET Framework

Understanding the Mono and Xamarin projects

Understanding .NET Core

Understanding .NET Standard

Understanding .NET Native

Comparing .NET technologies

Writing and compiling code using the .NET Core CLI tool

Writing code using a simple text editor

If you are using Windows Notepad

If you are using macOS TextEdit

Creating and compiling apps using the .NET Core CLI tool

Creating a console application at Command Prompt

Restoring packages, compiling code, and running the application

Fixing compiler errors

Understanding intermediate language

Writing and compiling code using Visual Studio 2017

Writing code using Microsoft Visual Studio 2017

Compiling code using Visual Studio 2017

Fixing mistakes with the error list

Adding existing projects to Visual Studio 2017

Autoformatting code

Experimenting with C# Interactive

Other useful windows

Writing and compiling code using Visual Studio Code

Writing code using Visual Studio Code

Compiling code using Visual Studio Code

Autoformatting code

Writing and compiling code using Visual Studio for Mac

Next steps

Managing source code with GitHub

Using Git with Visual Studio 2017

Using the Team Explorer window

Cloning a GitHub repository

Managing a GitHub repository

Using Git with Visual Studio Code

Configuring Git at the command line

Managing Git with Visual Studio Code

Practicing and exploring

Exercise 1.1 – Test your knowledge

Exercise 1.2 – Practice C# anywhere

Exercise 1.3 – Explore topics

Summary

Part 1, C# 7.1

Speaking C#

Understanding C# basics

Using Visual Studio 2017

Using Visual Studio Code on macOS, Linux, or Windows

C# grammar

Statements

Comments

Blocks

C# vocabulary

Help for writing correct code

Verbs are methods

Nouns are types, fields, and variables

Revealing the extent of the C# vocabulary

Building and running with Visual Studio 2017

Building and running with Visual Studio Code

Adding more types with Visual Studio 2017 and Visual Studio Code

Declaring variables

Naming variables

Literal values

Storing text

Storing numbers

Storing whole numbers

C# 7 improvements

Storing real numbers

Using Visual Studio 2017

Using Visual Studio Code

Writing code to explore numbers

Comparing double and decimal types

Storing Booleans

The object type

The dynamic type

Local variables

Specifying the type of a local variable

Inferring the type of a local variable

Making a value type nullable

Understanding nullable reference types

The billion-dollar mistake

Changing the defaults for nullable types in C# 8.0

Checking for null

Storing multiple values in an array

Exploring console applications further

Displaying output to the user

Getting input from the user

Importing a namespace

Simplifying the usage of the console

Reading arguments and working with arrays

Passing arguments with Visual Studio 2017

Passing arguments with Visual Studio Code

Viewing the output

Enumerating arguments

Running on Windows

Running on macOS

Handling platforms that do not support an API

Operating on variables

Experimenting with unary operators

Experimenting with arithmetic operators

Comparison and Boolean operators

Practicing and exploring

Exercise 2.1 – Test your knowledge

Exercise 2.2 – Practice number sizes and ranges

Exercise 2.3 – Explore topics

Summary

Controlling the Flow and Converting Types

Selection statements

Using Visual Studio 2017

Using Visual Studio Code on macOS, Linux, or Windows

The if statement

The code

Pattern matching with the if statement

The switch statement

The code

Pattern matching with the switch statement

Iteration statements

The while statement

The do statement

The for statement

The foreach statement

Casting and converting between types

Casting from numbers to numbers

Casting numbers implicitly

Casting numbers explicitly

Using the convert type

Rounding numbers

Converting from any type to a string

Converting from a binary object to a string

Parsing from strings to numbers or dates and times

Handling exceptions when converting types

The try statement

Catching all exceptions

Catching specific exceptions

Checking for overflow

The checked statement

The unchecked statement

Looking for help

Microsoft Docs and MSDN

Go to definition

Stack Overflow

Google

Subscribing to blogs

Design patterns

Singleton pattern

Practicing and exploring

Exercise 3.1 – Test your knowledge

Exercise 3.2 – Explore loops and overflow

Exercise 3.3 – Practice loops and operators

Exercise 3.4 – Practice exception handling

Exercise 3.5 – Explore topics

Summary

Writing, Debugging, and Testing Functions

Writing functions

Writing a times table function

Writing a function that returns a value

Writing mathematical functions

Formatting numbers for output

Calculating factorials with recursion

Debugging an application during development

Creating an application with a deliberate bug

Setting a breakpoint

The debugging toolbar

Debugging windows

Stepping through code

Customizing breakpoints

Logging during development and runtime

Instrumenting with Debug and Trace

Writing to the default trace listener

Configuring trace listeners

Switching trace levels

Unit testing functions

Creating a class library that needs testing with Visual Studio 2017

Creating a unit test project with Visual Studio 2017

Creating a class library that needs testing with Visual Studio Code

Writing unit tests

Running unit tests with Visual Studio 2017

Running unit tests with Visual Studio Code

Practicing and exploring

Exercise 4.1 – Test your knowledge

Exercise 4.2 – Practice writing functions with debugging and unit testing

Exercise 4.3 – Explore topics

Summary

Building Your Own Types with Object-Oriented Programming

Talking about OOP

Building class libraries

Creating a class library with Visual Studio 2017

Creating a class library with Visual Studio Code

Defining a class

Instantiating a class

Referencing an assembly using Visual Studio 2017

Referencing an assembly using Visual Studio Code

Importing a namespace

Managing multiple projects with Visual Studio Code

Inheriting from System.Object

Storing data with fields

Defining fields

Understanding access modifiers

Storing a value using the enum keyword

Storing multiple values using collections

Making a field static

Making a field constant

Making a field read-only

Initializing fields with constructors

Setting fields with default literal

Writing and calling methods

Combining multiple values with tuples

Defining methods with tuples

Naming the fields of a tuple

Inferring tuple names

Deconstructing tuples

Defining and passing parameters to methods

Overloading methods

Optional parameters and named arguments

Controlling how parameters are passed

Splitting classes using partial

Controlling access with properties and indexers

Defining read-only properties

Defining settable properties

Defining indexers

Practicing and exploring

Exercise 5.1 – Test your knowledge

Exercise 5.2 – Explore topics

Summary

Implementing Interfaces and Inheriting Classes

Setting up a class library and console application

Using Visual Studio 2017

Using Visual Studio Code

Defining the classes

Simplifying methods with operators

Implementing some functionality with a method

Implementing some functionality with an operator

Defining local functions

Raising and handling events

Calling methods using delegates

Defining events

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 or Visual Studio Code

Implementing interfaces

Common interfaces

Comparing objects when sorting

Attempting to sort objects without a method to compare

Defining a method to compare

Defining a separate comparer

Making types more reusable with generics

Making a generic type

Making a generic method

Managing memory with reference and value types

Defining a struct type

Releasing unmanaged resources

Ensuring that dispose is called

Inheriting from classes

Extending classes

Hiding members

Overriding members

Using Visual Studio 2017

Using Visual Studio 2017 or Visual Studio Code

Preventing inheritance and overriding

Polymorphism

Casting within inheritance hierarchies

Implicit casting

Explicit casting

Handling casting exceptions

Inheriting and extending .NET types

Inheriting from an exception

Extending types when you can't inherit

Using static methods to reuse functionality

Using extension methods to reuse functionality

Practicing and exploring

Exercise 6.1 – Test your knowledge

Exercise 6.2 – Practice creating an inheritance hierarchy

Exercise 6.3 – Explore topics

Summary

Part 2 – .NET Core 2.0 and .NET Standard 2.0

Understanding and Packaging .NET Standard Types

Understanding assemblies and namespaces

Base Class Libraries and CoreFX

Assemblies, NuGet packages, and platforms

Namespaces

Understanding dependent assemblies

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Relating assemblies and namespaces

Browsing assemblies with Visual Studio 2017

Using Visual Studio 2017 or Visual Studio Code

Importing a namespace

Relating C# keywords to .NET types

Sharing code cross-platform with .NET Standard 2.0 class libraries

Creating a .NET Standard 2.0 class library

Using Visual Studio 2017

Using Visual Studio Code

Understanding NuGet packages

Understanding metapackages

Understanding frameworks

Fixing dependencies

Publishing your applications for deployment

Creating a console application to publish

Publishing with Visual Studio 2017 on Windows

Publishing with Visual Studio Code on macOS

Packaging your libraries for NuGet distribution

Understanding dotnet commands

Adding a package reference

Using Visual Studio Code

Using Visual Studio 2017

Packaging a library for NuGet

Testing your package

Using Visual Studio Code

Using Visual Studio 2017

Using Visual Studio 2017 and Visual Studio Code

Porting from .NET Framework to .NET Core

Could you port?

Should you port?

Differences between .NET Framework and .NET Core

Understanding the .NET Portability Analyzer

Using non-.NET Standard libraries

Practicing and exploring

Exercise 7.1 – Test your knowledge

Exercise 7.2 – Explore topics

Summary

Using Common .NET Standard Types

Working with numbers

Working with big integers

Working with complex numbers

Working with text

Getting the length of a string

Getting the characters of a string

Splitting a string

Getting part of a string

Checking a string for content

Other string members

Building strings efficiently

Pattern matching with regular expressions

The syntax of a regular expression

Examples of regular expressions

Working with collections

Common features of all collections

Understanding collections

Lists

Dictionaries

Stacks

Queues

Sets

Working with lists

Working with dictionaries

Sorting collections

Using specialized collections

Using immutable collections

Working with network resources

Working with URIs, DNS, and IP addresses

Pinging a server

Working with types and attributes

Versioning of assemblies

Reading assembly metadata

Creating custom attributes

Doing more with reflection

Internationalizing your code

Globalizing an application

Practicing and exploring

Exercise 8.1 – Test your knowledge

Exercise 8.2 – Practice regular expressions

Exercise 8.3 – Practice writing extension methods

Exercise 8.4 – Explore topics

Summary

Working with Files, Streams, and Serialization

Managing the filesystem

Handling cross-platform environments and filesystems

Using Windows 10

Using macOS

Managing drives

Managing directories

Managing files

Managing paths

Getting file information

Controlling files

Reading and writing with streams

Writing to text and XML streams

Writing to text streams

Writing to XML streams

Disposing of file resources

Implementing disposal with try statement

Simplifying disposal with the using statement

Compressing streams

Encoding text

Encoding strings as byte arrays

Encoding and decoding text in files

Serializing object graphs

Serializing with XML

Deserializing with XML

Customizing the XML

Serializing with JSON

Serializing with other formats

Practicing and exploring

Exercise 9.1 – Test your knowledge

Exercise 9.2 – Practice serializing as XML

Exercise 9.3 – Explore topics

Summary

Protecting Your Data and Applications

Understanding the vocabulary of protection

Keys and key sizes

IVs and block sizes

Salts

Generating keys and IVs

Encrypting and decrypting data

Encrypting symmetrically with AES

Using Visual Studio 2017

Using Visual Studio Code

Creating the Protector class

Hashing data

Hashing with the commonly used SHA256

Signing data

Signing with SHA256 and RSA

Testing the signing and validating

Generating random numbers

Generating random numbers for games

Generating random numbers for cryptography

Testing the random key or IV generation

Authenticating and authorizing users

Implementing authentication and authorization

Testing authentication and authorization

Protecting application functionality

Practicing and exploring

Exercise 10.1 – Test your knowledge

Exercise 10.2 – Practice protecting data with encryption and hashing

Exercise 10.3 – Practice protecting data with decryption

Exercise 10.4 – Explore topics

Summary

Working with Databases Using Entity Framework Core

Understanding modern databases

Using a sample relational database

Using Microsoft SQL Server

Connecting to SQL Server

Creating the Northwind sample database for SQL Server

Managing the Northwind sample database with Server Explorer

Using SQLite

Creating the Northwind sample database for SQLite

Managing the Northwind sample database with SQLiteStudio

Setting up Entity Framework Core

Choosing an EF Core data provider

Connecting to the database

Using Visual Studio 2017

Using Visual Studio Code

Defining Entity Framework Core models

EF Core conventions

EF Core annotation attributes

EF Core Fluent API

Building an EF Core model

Defining the Category entity class

Defining the Product entity class

Defining the Northwind database context class

Querying an EF Core model

Logging EF Core

Pattern matching with Like

Defining global filters

Loading patterns with EF Core

Eager and lazy loading entities

Explicit loading entities

Manipulating data with EF Core

Inserting entities

Updating entities

Deleting entities

Pooling database contexts

Transactions

Defining an explicit transaction

Practicing and exploring

Exercise 11.1 – Test your knowledge

Exercise 11.2 – Practice exporting data using different serialization formats

Exercise 11.3 – Explore the EF Core documentation

Summary

Querying and Manipulating Data Using LINQ

Writing LINQ queries

Extending sequences with the enumerable class

Filtering entities with Where

Targeting a named method

Simplifying the code by removing the explicit delegate instantiation

Targeting a lambda expression

Sorting entities

Sorting by a single property using OrderBy

Sorting by a subsequent property using ThenBy

Filtering by type

Working with sets

Using LINQ with EF Core

Projecting entities with Select

Building an EF Core model

Joining and grouping

Aggregating sequences

Sweetening the syntax with syntactic sugar

Using multiple threads with parallel LINQ

Creating your own LINQ extension methods

Working with LINQ to XML

Generating XML using LINQ to XML

Reading XML using LINQ to XML

Practicing and exploring

Exercise 12.1 – Test your knowledge

Exercise 12.2 – Practice querying with LINQ

Exercise 12.3 – Explore topics

Summary

Improving Performance and Scalability Using Multitasking

Monitoring performance and resource usage

Evaluating the efficiency of types

Monitoring performance and memory use

Using Visual Studio 2017

Using Visual Studio Code

Creating the Recorder class

Measuring the efficiency of processing strings

Understanding processes, threads, and tasks

Running tasks asynchronously

Running multiple actions synchronously

Running multiple actions asynchronously using tasks

Waiting for tasks

Continuing with another task

Nested and child tasks

Synchronizing access to shared resources

Accessing a resource from multiple threads

Applying a mutually exclusive lock to a resource

Understanding the lock statement

Making operations atomic

Applying other types of synchronization

Understanding async and await

Improving responsiveness for console apps

Improving responsiveness for GUI apps

Improving scalability for web applications and web services

Common types that support multitasking

await in catch blocks

Practicing and exploring

Exercise 13.1 – Test your knowledge

Exercise 13.2 – Explore topics

Summary

Part 3 – App Models

Building Web Sites Using ASP.NET Core Razor Pages

Understanding web development

Understanding HTTP

Client-side web development

Understanding ASP.NET Core

Classic ASP.NET versus modern ASP.NET Core

Creating an ASP.NET Core project with Visual Studio 2017

Creating an ASP.NET Core project with Visual Studio Code

Reviewing the ASP.NET Core Empty project template

Testing the empty website

Enabling static files

Enabling default files

Exploring Razor Pages

Enabling Razor Pages

Defining a Razor Page

Using shared layouts with Razor Pages

Setting a shared layout

Defining a shared layout

Using code-behind files with Razor Pages

Using Entity Framework Core with ASP.NET Core

Creating Entity models for Northwind

Creating a class library for the Northwind entity classes

Defining the entity classes

Creating a class library for Northwind database context

Using Visual Studio 2017

Using Visual Studio Code

Defining the database context class

Creating the Northwind database in the website

Configure Entity Framework Core as a service

Manipulating data

Practicing and exploring

Exercise 14.1 – Practice building a data-driven website

Exercise 14.2 – Explore topics

Summary

Building Web Sites Using ASP.NET Core MVC

Setting up an ASP.NET Core MVC website

Creating an ASP.NET Core MVC website

Using Visual Studio 2017

Using Visual Studio Code

Reviewing the ASP.NET Core MVC project template

Performing database migrations

Using Visual Studio 2017

Using Visual Studio Code

Testing the ASP.NET MVC website

Reviewing authentication with ASP.NET Identity

Understanding an ASP.NET Core MVC website

ASP.NET Core startup

Understanding the default route

Understanding ASP.NET Core MVC controllers

Understanding ASP.NET Core MVC models

Configuring an EF Core entity data model

Creating view models for requests

Fetch the model in the controller

Understanding ASP.NET Core MVC views

Rendering the Home controller's views

Sharing layouts between views

Defining custom styles

Defining a typed view

Passing parameters using a route value

Passing parameters using a query string

Practicing and exploring

Exercise 15.1 – Practice improving scalability by understanding and implementing async action methods

Exercise 15.2 – Explore topics

Summary

Building Web Services and Applications Using ASP.NET Core

Building web services using ASP.NET Core Web API

Understanding ASP.NET Core controllers

Creating an ASP.NET Core Web API project

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Creating a web service for the Northwind database

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Creating data repositories for entities

Configuring and registering the customers repository

Creating the Web API controller

Documenting and testing web services using Swagger

Testing GET requests with any browser

Testing POST, PUT, and DELETE requests with Swagger

Installing a Swagger package

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Testing GET requests with Swagger UI

Testing POST requests with Swagger UI

Building SPAs using Angular

Understanding the Angular project template

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Calling NorthwindService

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Modifying the home component to call NorthwindService

Testing the Angular component calling the service

Using Visual Studio 2017

Using Visual Studio Code

Using Visual Studio 2017 and Visual Studio Code

Using other project templates

Installing additional template packs

Practicing and exploring

Exercise 16.1 – Practice with React and Redux

Exercise 16.2 – Explore topics

Summary

Building Windows Apps Using XAML and Fluent Design

Understanding the modern Windows platform

Understanding Universal Windows Platform

Understanding Fluent Design System

Filling user interface elements with acrylic brushes

Connecting user interface elements with animations

Parallax views and Reveal lighting

Understanding XAML Standard 1.0

Simplifying code using XAML

Choosing common controls

Creating a modern Windows app

Enabling developer mode

Creating a UWP project

Exploring common controls and acrylic brushes

Exploring Reveal

Installing more controls

Using resources and templates

Sharing resources

Replacing a control template

Data binding

Binding to elements

Binding to data sources

Modifying the NorthwindService

Creating the Northwind app

Building apps using Windows Template Studio

Installing Windows Template Studio

Selecting project types, frameworks, pages, and features

Retargeting the project

Customizing some views

Testing the app's functionality

Practicing and exploring

Exercise 17.1 – Explore topics

Summary

Building Mobile Apps Using XAML and Xamarin.Forms

Understanding Xamarin and Xamarin.Forms

How Xamarin.Forms extends Xamarin

Mobile first, cloud first

Building mobile apps using Xamarin.Forms

Adding Android SDKs

Creating a Xamarin.Forms solution

Creating a model

Creating an interface for dialing phone numbers

Implement the phone dialer for iOS

Implement the phone dialer for Android

Creating views for the customers list and customer details

Creating the view for the list of customers

Creating the view for the customer details

Testing the mobile app with iOS

Adding NuGet packages for calling a REST service

Getting customers from the service

Practicing and exploring

Exercise 18.1 - Explore topics

Summary

Summary

Good luck!

Answers to the Test Your Knowledge Questions

Chapter 1 – Hello, C#! Welcome, .NET Core!

Chapter 2 – Speaking C#

Chapter 3 – Controlling the Flow and Converting Types

Chapter 4 – Writing, Debugging, and Testing Functions

Chapter 5 – Building Your Own Types with Object-Oriented Programming

Chapter 6 – Implementing Interfaces and Inheriting Classes

Chapter 7 – Understanding and Packaging .NET Standard Types

Chapter 8 – Using Common .NET Standard Types

Chapter 9 – Working with Files, Streams, and Serialization

Chapter 10 – Protecting Your Data and Applications

Chapter 11 – Working with Databases Using Entity Framework Core

Chapter 12 – Querying and Manipulating Data Using LINQ

Chapter 13 – Improving Performance and Scalability Using Multitasking

Preface

There are C# books that are thousands of pages long that aim to be comprehensive references to the C# programming language and the .NET Framework.

This book is different. It is concise and aims to be a fast-paced read that is packed with hands-on walkthroughs. I wrote this book to be the best step-by-step guide to learning modern cross-platform C# proven practices using .NET Core.

I will point out the cool corners and gotchas of C#, so you can impress colleagues and employers and get productive fast. Rather than slowing down and boring some readers by explaining every little thing, I will assume that if a term I use is new to you, then you will know how to Google an answer.

At the end of each chapter is a section titled Practice and explore, in which you will complete hands-on practical exercises and explore topics deeper on your own with a little nudge in the right direction from me.

You can download solutions for the exercises from the following GitHub repository. I will provide instructions on how to do this using Visual Studio 2017 and Visual Studio Code at the end of Chapter 1, Hello, C#! Welcome, .NET Core!

https://github.com/markjprice/cs7dotnetcore2

What this book covers

Chapter 1, Hello, C#! Welcome, .NET Core!, is about setting up your development environment and using various tools to create the simplest application possible with C#. You will learn how to write and compile code using Visual Studio 2017 on Windows; Visual Studio Code on macOS, Linux, or Windows; or Visual Studio for Mac on macOS. You will learn the different .NET technologies: .NET Framework, .NET Core, .NET Standard, and .NET Native.

Part 1 – C# 7.1

Chapter 2, Speaking C#, explains the grammar and vocabulary that you will use every day to write the source code for your applications. In particular, you will learn how to declare and work with variables of different types.

Chapter 3, Controlling the Flow and Converting Types, talks about writing code that makes decisions, repeats a block of statements, and converts between types, and writing code defensively to handle errors when they inevitably occur. You will also learn the best places to look for help.

Chapter 4, Writing, Debugging, and Testing Functions, is about following the Don't Repeat Yourself (DRY) principle by writing reusable functions, and learning how to use debugging tools to track down and remove bugs, monitoring your code while it executes to diagnose problems, and rigorously testing your code to remove bugs and ensure stability and reliability before it gets deployed into production.

Chapter 5, Building Your Own Types with Object-Oriented Programming, discusses all the different categories of members that a type can have, including fields to store data and methods to perform actions. You will use OOP concepts, such as aggregation and encapsulation. You will learn the C# 7 language features such as tuple syntax support and out variables, and C# 7.1 language features such as default literals and inferred tuple names.

Chapter 6, Implementing Interfaces and Inheriting Classes, explains deriving new types from existing ones using object-oriented programming (OOP). You will learn how to define operators and C# 7 local functions, delegates and events, how to implement interfaces about base and derived classes, how to override a type member, how to use polymorphism, how to create extension methods, and how to cast between classes in an inheritance hierarchy.

Part 2 – .NET Core 2.0 and .NET Standard 2.0

Chapter 7, Understanding and Packaging .NET Standard Types, presents .NET Core 2.0 types that are part of .NET Standard 2.0, and how they are related to C#.  You will learn how to deploy and package your own apps and libraries.

Chapter 8, Using Common .NET Standard Types, discusses the .NET Standard types that allow your code to perform common practical tasks, such as manipulating numbers and text, storing items in collections, and implementing internationalization.

Chapter 9, Working with Files, Streams, and Serialization, talks about interacting with the filesystem, reading and writing to files and streams, text encoding, and serialization.

Chapter 10, Protecting Your Data and Applications, is about protecting your data from being viewed by malicious users using encryption and from being manipulated or corrupted using hashing and signing. You will also learn about authentication and authorization to protect applications from unauthorized uses.

Chapter 11, Working with Databases Using Entity Framework Core, explains reading and writing to databases, such as Microsoft SQL Server and SQLite, using the object-relational mapping technology named Entity Framework Core.

Chapter 12, Querying and Manipulating Data Using LINQ, teaches you Language INtegrated Query (LINQ)—language extensions that add the ability to work with sequences of items and filter, sort, and project them into different outputs.

Chapter 13, Improving Performance and Scalability Using Multitasking, discusses allowing multiple actions to occur at the same time to improve performance, scalability, and user productivity. You will learn about the C# 7.1 async Main feature, and how to use types in the System.Diagnostics namespace to monitor your code to measure performance and efficiency.

Part 3 – App Models

Chapter 14, Building Web Sites Using ASP.NET Core Razor Pages, is about learning the basics of building websites with a modern HTTP architecture on the server-side using ASP.NET Core. You will learn the new ASP.NET Core feature known as Razor Pages that simplifies creating web pages for small web sites.

Chapter 15,Building Web Sites Using ASP.NET Core MVC, is about learning how to build large, complex websites in a way that is easy to unit test and manage with teams of programmers using ASP.NET Core. You will learn about startup configuration, authentication, routes, models, views, and controllers in ASP.NET Core MVC.

Chapter 16, Building Web Services and Applications Using ASP.NET Core, explains building web applications with a combination of a modern frontend technology, such as Angular or React, and a backend REST architecture web service using ASP.NET Core Web API.

Chapter 17, Building Windows Apps Using XAML and Fluent Design, talks about learning the basics of XAML that can be used to define the user interface for a graphical app for the Universal Windows Platform (UWP), and applying principles and features of Fluent Design to light it up. This app can then run on any device running Windows 10, Xbox One, and even Mixed Reality devices such as HoloLens.

Chapter 18, Building Mobile Apps Using XAML and Xamarin.Forms, discusses introducing you to taking C# mobile by building a cross-platform app for iOS and Android. The client-side mobile app will be created with Visual Studio for Mac using XAML and Xamarin.Forms.

Appendix, Answers to the Test Your Knowledge Questions, has the answers to the test questions at the end of each chapter.

What you need for this book

You can develop and deploy C# on many platforms, including Windows, macOS, and many varieties of Linux. For the best programming experience, and to reach the most platforms, I recommend that you learn the basics of all members of the Visual Studio family: Visual Studio 2017, Visual Studio Code, and Visual Studio for Mac.

My recommendation for the operating system and development tool combinations is as follows:

Visual Studio 2017 on 

Windows 10

Visual Studio for Mac on 

macOS

Visual Studio Code on 

Windows 10 or macOS

The best version of Windows to use is Microsoft Windows 10 because you will need this version to create Universal Windows Platform apps in Chapter 17, Building Windows Apps Using XAML and Fluent Design. Earlier versions of Windows, such as 7 or 8.1, will work for the other chapters.

The best version of macOS to use is Sierra or High Sierra because you will need macOS to build iOS mobile apps in Chapter 18,Building Mobile Apps Using XAML and Xamarin.Forms. Although you can use Visual Studio 2017 on Windows to write the code for iOS and Android mobile apps, you must have macOS and Xcode to compile them.

Who this book is for

If you have heard that C# is a popular general-purpose programming language used to create every type of software, ranging from web applications and services, to business applications and games, then this book is for you.

If you have heard that C# can create software that runs on a wide range of devices, from desktop to server, from mobile to gaming systems such as Xbox One, then this book is for you.

If you have heard that .NET Core is Microsoft's bet on a cross-platform .NET future, optimized for server-side web development in the cloud, and Augmented Reality (AR) or Virtual Reality (VR) devices such as HoloLens, then this book is for you.

If you have heard that Microsoft has a popular cross-platform developer tool named Visual Studio Code that creates these cross-platform apps, and you are curious to try it, then this book is for you.

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Hello, C#! Welcome, .NET Core!

This chapter is about setting up your development environment, understanding the similarities and differences between .NET Core, .NET Framework, .NET Standard, and .NET Native, and using various tools to create the simplest application possible with C# and .NET Core.

Most people learn complex topics by imitation and repetition rather than reading a detailed explanation of theory. So, I will not explain every keyword and step. The idea is to get you to write some code, build an application, and see it run. You don't need to know the details of how it all works yet.

In the words of Samuel Johnson, author of the English dictionary in 1755, I have likely committed "a few wild blunders, and risible absurdities, from which no work of such multiplicity is free." I take sole responsibility for these and hope you appreciate the challenge of my attempt to lash the wind by writing this book about .NET Core and its command-line tooling during its rocky birth during 2016 and 2017.

This chapter covers the following topics:

Setting up

your development environment

Understanding .NET

Writing and compiling code using the .NET Core CLI tool

Writing and compiling code using Visual Studio 2017

Writing and compiling code using Visual Studio Code

Writing and compiling code using Visual Studio for Mac

Managing source code with GitHub

Setting up your development environment

Before you start programming, you will need to choose an Integrated Development Environment (IDE) that includes a code editor for C#. Microsoft has a family of IDEs:

Visual Studio 2017

Visual Studio for Mac

Visual Studio Code

The most mature and fully-featured IDE to choose is Microsoft Visual Studio 2017, but it only runs on the Windows operating system.

The most modern and lightweight IDE to choose, and the only one from Microsoft that is cross-platform, is Microsoft Visual Studio Code, and it will run on all common operating systems, including Windows, macOS, and many varieties of Linux, such as Red Hat Enterprise Linux (RHEL) and Ubuntu.

To help you decide if Visual Studio Code is right for you, I recommend that you watch the following video, Beginner's Guide to VS Code: Up and Running in Ten Minutes:https://channel9.msdn.com/Blogs/raw-tech/Beginners-Guide-to-VS-Code

The most suitable IDE to choose for mobile development is Visual Studio for Mac. To create apps for iOS (iPhone and iPad), tvOS, macOS, and watchOS, you must have macOS and Xcode. Although you can use Visual Studio 2017 with its Xamarin extensions to write a cross-platform mobile app, you still need macOS and Xcode to compile it.

The following table shows which IDE and operating systems can or must be used for each of the chapters in this book:

Chapters

IDE

Operating systems

Chapters 1 to 16

Visual Studio 2017

Windows 7 SP1 or later

Chapters 1 to 16

Visual Studio Code

Windows, macOS, Linux

Chapters 1 to 16

Visual Studio for Mac

macOS

Chapter 17

Visual Studio 2017

Windows 10

Chapter 18

Visual Studio for Mac

macOS

Good Practice If you have the option, then I recommend that you try all the coding exercises with Visual Studio 2017 on Windows, Visual Studio Code on macOS, Linux, or Windows, and Visual Studio for Mac. It will be good for you to get experience with C# and .NET Core on a variety of operating systems and development tools.

To write the third edition of this book, I used the following listed software, as shown in the following screenshot:

Visual Studio 2017 on Windows 10 in a virtual machine

Visual Studio for Mac on macOS

Visual Studio Code on macOS

Visual Studio Code on RHEL (not shown in screenshot)

Using alternative C# IDEs

There are alternative IDEs for C#, for example, MonoDevelop and JetBrains Rider. You can install either of these two IDEs with the help of the following URLs:

For MonoDevelop IDE, visit

http://www.monodevelop.com/

For JetBrains Rider, visit

https://www.jetbrains.com/rider/

Cloud9 is a web browser-based IDE, so it's even more cross-platform than the others. It is growing in popularity. Here is the link: https://c9.io/web/sign-up/free

Deploying cross-platform

Your choice of IDE and operating system for development does not limit where your code gets deployed. .NET Core 2.0 supports the following platforms for deployment:

Windows 7 SP1, or later

Windows Server 2008 R2 SP1, or later

Windows IoT 10, or later

macOS Sierra (version 10.12), or later

RHEL 7.3, or later

Ubuntu 14.04, or later

Fedora 25, or later

Debian 8.7, or later

openSUSE 42.2, or later

Tizen 4, or later

Linux OSes are popular server host platforms because they are relatively lightweight and more cost-effectively scalable when compared to operating system platforms such as Windows and macOS.

In the next section, you will install Microsoft Visual Studio 2017 for Windows. If you prefer to use Microsoft Visual Studio Code, jump ahead to the Installing Microsoft Visual Studio Code for Windows, macOS, or Linuxsection.If you prefer to use Microsoft Visual Studio for Mac, jump ahead to theInstalling Microsoft Visual Studio for Macsection.

Installing Microsoft Visual Studio 2017

You can use Windows 7 SP1 or later to complete most of the chapters in this book, but you will have a better experience if you use Windows 10 Fall Creators Update.

Since October 2014, Microsoft has made a professional-quality edition of Visual Studio available to everyone for free. It is called Community Edition.

Download and install Microsoft Visual Studio 2017 version 15.4 or later from the following link:

https://www.visualstudio.com/downloads/

You must install version 15.4 or later of Visual Studio 2017 to be able to work with .NET Core for UWP. You must install version 15.3 or later of Visual Studio 2017 to be able to work with .NET Core 2.0. Older versions of Visual Studio 2017 only support .NET Core 1.0 and 1.1.

Choosing workloads

On the Workloads tab, choose the following, as partially shown in the following screenshot:

Universal Windows Platform development

.NET desktop development

ASP.NET and web development

Azure development

Node.js development

.NET Core cross-platform development

Choosing additional components

On the Individual components tab, choose the following additional components:

Class Designer

GitHub extension for Visual Studio

PowerShell tools

Click on Install, and wait for the installer to acquire the selected software, and install it. When the installation is complete, click on Launch.

While you wait for Visual Studio 2017 to install, you can jump ahead to the Understanding .NET section in this chapter.

The first time that you run Visual Studio 2017, you will be prompted to sign in. If you have a Microsoft account, you can use that account. If you don't, then register for a new one at the following link:

https://signup.live.com/

When starting Visual Studio 2017 for the first time, you will be prompted to configure your environment. For Development Settings, choose Visual C#. For the color theme, I chose Blue, but you can choose whatever tickles your fancy.

You will see the Microsoft Visual Studio user interface with the Start Page open in the central area. Like most Windows desktop applications, Visual Studio has a menu bar, a toolbar for common commands, and a status bar at the bottom. On the right is the Solution Explorer that will list your open projects:

To have quick access to Visual Studio in the future, right-click on its entry in the Windows taskbar and select Pin this program to taskbar.

InChapter 14,Building Web Sites Using ASP.NET Core Razor Pages,Chapter 15, Building Web Sites Using ASP.NET Core MVC,andChapter 16,Building Web Services and Applications Using ASP.NET Core,you will need Node.js and NPM installed.

Download the Node.js installer for Windows from the following link:

https://nodejs.org/en/download/

Run the Node.js installer, as shown in the following screenshot:

Installing Microsoft Visual Studio Code

Between June 2015 and September 2017, Microsoft released a new version of Visual Studio Code almost every month. Visual Studio Code has rapidly improved and surprised Microsoft with its popularity. Even if you plan to use Visual Studio 2017 or Visual Studio for Mac as your primary development tool, I recommend that you learn how to use Visual Studio Code and the .NET Core command-line tool as well.

You can download Visual Studio Code from the following link:

https://code.visualstudio.com/

You can read about Microsoft's plans for Visual Studio Code in 2018 at the following link:https://github.com/Microsoft/vscode/wiki/Roadmap

Installing Microsoft Visual Studio Code for macOS

In this book, I will show examples and screenshots of Visual Studio Code using the version for macOS. The steps for doing the same with Visual Studio Code for Windows and variants of Linux is very similar, so I will not repeat the instructions for every platform.

After downloading Visual Studio Code for macOS, drag and drop it to your Applications folder, as shown in the following screenshot:

You will now need to install the .NET Core SDK for macOS. The full instructions, including a video to watch, are described at the following link, and I have included the basic steps in this book for your convenience: https://www.microsoft.com/net/core#macos

The first step is to install Homebrew (if you don't already have it).

Start macOS's Terminal app and enter the following command at the prompt:

/usr/bin/ruby -e "$(curl -fsSLhttps://raw.githubusercontent.com/Homebrew/install/master/install)"

Terminal will prompt you to press Enter to continue and then prompt for your password.

If you are using .NET Core 1.0 or 1.1, then at this point you will need to use Homebrew to install OpenSSL, which is a dependency of older versions of .NET Core on macOS.

Installing .NET Core SDK for macOS

The next step is to download the .NET Core SDK installer for macOS (x64) from the following link:

https://www.microsoft.com/net/download/core

Run the dotnet-sdk-2.0.0-sdk-osx-x64.pkg installer package, as shown in the following screenshot:

Click on Continue, accept the license agreement, click on Install, and then, once it has finished, click on Close.

Installing Node Package Manager for macOS

In Chapter 14, Building Web Sites Using ASP.NET Core Razor Pages, Chapter 15,Building Web Sites Using ASP.NET Core MVC,andChapter 16,Building Web Services and Applications Using ASP.NET Core, you will need Node.js and NPM installed.

In Terminal, enter commands to install Node.js and NPM, and then check their versions, which at the time I wrote this book, were Node.js version 8.4 and NPM version 5.3, as shown in the following screenshot:

brew install node

node -v

npm -v

Installing the Visual Studio Code extension for C#

The C# for Visual Studio Code extension is not necessary, but it provides IntelliSense as you type, so it's very handy to install.

Launch Visual Studio Code and click on the Extensions icon, or go to View | Extensions, or press Cmd + Shift + X.

C# is the most popular extension, so you should see it at the top of the list, as shown in the following screenshot:

Click on Install, and then click on Reload, to reload the window and activate the extension.

Installing Visual Studio for Mac

In November 2016, Microsoft released a preview version of Visual Studio for Mac. Initially, it could only be used to create Xamarin mobile apps, because it is a fork of the Xamarin Studio product. The final release version, available since May 2017, has support for creating .NET Standard 2.0 class libraries, ASP.NET Core web applications and services, and console apps, so it can be used to complete (almost) all of the exercises in this book.

Although Visual Studio 2017 on Windows can be used to create mobile apps for iOS and Android, only Xcode running on macOS or OS X can compile iOS apps, so it is my opinion that a developer might as well use the native Visual Studio for Mac to create mobile apps.

Installing Xcode

If you have not already installed Xcode on your Mac, install it now from the App Store.

On the Apple menu, choose App Store....

In the App Store, enter xcode in the Search box, and one of the first results will be Xcode, as shown in the following screenshot:

Click on Get, and wait for Xcode to install.

Downloading and installing Visual Studio for Mac

You can download and install Visual Studio for Mac from the following link:

https://www.visualstudio.com/vs/visual-studio-mac/

In the Visual Studio for MacInstaller, accept the License Terms and the Privacy Statement, choose to install all components, and then click on Continue, as shown in the following screenshot:

Click on Continue, and then click on Install.

Agree to the license terms for the components, such as the Android SDK, click on Continue, and wait for Visual Studio for Mac to fully install.

Start Visual Studio for Mac to see the Welcome Page, as shown in the following screenshot:

If you are prompted to update components, then click on Restart and Install Updates.

Now that you have installed and set up your development environment, you will learn some background about .NET before diving in to writing code.

Understanding .NET

.NET Framework, .NET Core, .NET Standard, and .NET Native are related and overlapping platforms for developers to build applications and services upon.

Understanding .NET Framework

Microsoft's .NET Framework is a development platform that includes a Common Language Runtime (CLR) that manages the execution of code, and provides a rich library of classes to build applications.

Microsoft designed .NET Framework to have the possibility of being cross-platform, but Microsoft put their implementation effort into making it work best with Windows.

Practically speaking, .NET Framework is Windows-only, and a legacy platform.

Understanding the Mono and Xamarin projects

Third parties developed a .NET implementation named the Mono project that you can read more about at the following link:http://www.mono-project.com/

Mono is cross-platform, but it fell well behind the official implementation of .NET Framework. It has found a niche as the foundation of the Xamarin mobile platform.

Microsoft purchased Xamarin in 2016 and now gives away what used to be an expensive Xamarin extension for free with Visual Studio 2017. Microsoft renamed the Xamarin Studio development tool to Visual Studio for Mac