ASP.NET Core in Action

714 Pages·2017·41.63 MB·English

M A N N I N G
Andrew Lock
Useful .NET CLI (dotnet) commands.
Use --help to see all the optional arguments
Command Description Run from
dotnet restore Restores the NuGet packages for all the Solution folder
projects in the solution.
dotnet build Builds all the projects in the solution. To Solution folder
build in Release mode, use the -c
switch.
dotnet run Runs the project in the current folder. Use Project folder
during development to run your app.
dotnet publish -c Release –o Publishes the project to the provided Project folder
<Folder> folder. This copies all the required files to
the provided output folder so that it can be
deployed.
dotnet test Builds the project and executes any unit Project folder
tests found in the project. Requires the
.NET Test SDK and a testing framework
adapter (see chapter 20).
dotnet add package <Name> Installs the NuGet package with the pro- Project folder
vided name into the current project.
Optionally, specify a package version, for
example -v 2.1.0.
dotnet new --list Views all the installed templates for creat- Anywhere
ing ASP.NET Core apps, libraries, test proj-
ects, solution files, and much more.
dotnet new --install Installs a new template from the provided Anywhere
<PackageName> NuGet package name. For example,
dotnet new --install
"NetEscapades.Templates::*".
dotnet new <Template> –o <Folder> Creates a new item from the provided tem- Anywhere, empty
-n <NewName> plate, specifying the folder in which to folder for new
place the item, and the name for the item. projects
dotnet ef --help Displays help for managing your database Project folder
and migrations using EF Core. Requires
the EF Core tools (see chapter 12).
dotnet ef migrations add <Name> Adds a new EF Core migration to the proj- Project folder
ect with the provided name.
dotnet ef database update Applies pending EF Core migrations to a Project folder
database. Warning—this will modify your
database!
ASP.NET Core in Action

ASP.NET
Core in Action
ANDREW LOCK
MANNING
SHELTER ISLAND
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1 2 3 4 5 6 7 8 9 10 – EBM – 23 22 21 20 19 18
brief contents
PART 1 GETTING STARTED WITH MVC..........................................1
1 ■ Getting started with ASP.NET Core 3
2 ■ Your first application 28
3 ■ Handling requests with the middleware pipeline 61
4 ■ Creating web pages with MVC controllers 93
5 ■ Mapping URLs to methods using conventional routing 120
6 ■ The binding model: retrieving and validating user input 148
7 ■ Rendering HTML using Razor views 174
8 ■ Building forms with Tag Helpers 204
9 ■ Creating a Web API for mobile and client applications
using MVC 234
PART 2 BUILDING COMPLETE APPLICATIONS..............................265
10 ■ Service configuration with dependency injection 267
11 ■ Configuring an ASP.NET Core application 303
12 ■ Saving data with Entity Framework Core 334
13 ■ The MVC filter pipeline 369
14 ■ Authentication: adding users to your application with
Identity 400
15 ■ Authorization: securing your application 432
16 ■ Publishing and deploying your application 461
v
vi BRIEF CONTENTS
PART 3 EXTENDING YOUR APPLICATIONS...................................499
17 ■ Monitoring and troubleshooting errors with logging 501
18 ■ Improving your application’s security 534
19 ■ Building custom components 572
20 ■ Testing your application 607
contents
preface xvii
acknowledgments xix
about this book xxi
about the author xxv
about the cover illustration xxvi
PART 1 GETTING STARTED WITH MVC...........................1
1 Getting started with ASP.NET Core 3
1.1 An introduction to ASP.NET Core 4
Using a web framework 4 ■ The benefits and limitations of
ASP.NET 5 ■ What is ASP.NET Core? 6
1.2 When to choose ASP.NET Core 8
What type of applications can you build? 8 ■ If you’re new to .NET
development 10 ■ If you’re a .NET Framework developer creating a
new application 12 ■ Converting an existing ASP.NET
application to ASP.NET Core 16
1.3 How does ASP.NET Core work? 17
How does an HTTP web request work? 17 ■ How does ASP.NET
Core process a request? 19
1.4 Choosing a platform for ASP.NET Core 21
Advantages of using .NET Framework 21 ■ Advantages of using
.NET Core 22
vii
viii CONTENTS
1.5 Preparing your development environment 23
If you’re a Windows user 24 ■ If you’re a Linux or
macOS user 25
2 Your first application 28
2.1 A brief overview of an ASP.NET Core application 29
2.2 Creating your first ASP.NET Core application 32
Using a template to get started 32 ■ Building the application 35
2.3 Running the web application 36
2.4 Understanding the project layout 38
2.5 The csproj project file: defining your dependencies 40
2.6 The Program class: building a web host 41
2.7 The Startup class: configuring your application 44
Adding and configuring services 45 ■ Defining how
requests are handled with middleware 47
2.8 MVC middleware and the home controller 52
2.9 Generating HTML with Razor template views 54
3 Handling requests with the middleware pipeline 61
3.1 What is middleware? 63
3.2 Combining middleware in a pipeline 66
Simple pipeline scenario 1: a holding page 67 ■ Simple pipeline
scenario 2: Handling static files 70 ■ Simple pipeline scenario 3:
An MVC web application 73
3.3 Handling errors using middleware 78
Viewing exceptions in development:
DeveloperExceptionPage 80 ■ Handling exceptions
in production: ExceptionHandlerMiddleware 82
Handling other errors: StatusCodePagesMiddleware 86
Disabling error handling middleware for Web APIs 90
4 Creating web pages with MVC controllers 93
4.1 An introduction to MVC 95
The MVC design pattern 95 ■ MVC in ASP.NET Core 98
Adding the MvcMiddleware to your application 104 ■ What
makes a controller a controller? 111
4.2 MVC controllers and action methods 113
Accepting parameters to action methods 114 ■ Using
ActionResult 116