ASP.NET Core Identity Documentation

ASP.NET Core Identity

ASP.NET Core Identity is a membership system that provides user identity features for web applications and services. It includes features for user registration, login, password reset, and more. This document provides a comprehensive guide to using ASP.NET Core Identity.

Getting Started with ASP.NET Core Identity

This section covers the basic setup and configuration of ASP.NET Core Identity in your project. You'll learn how to add the necessary NuGet packages and configure the Identity services in your application's startup class.

To get started, you need to install the following NuGet packages:

dotnet add package Microsoft.AspNetCore.Identity.EntityFrameworkCore
dotnet add package Microsoft.AspNetCore.Identity.UI

In your Program.cs (or Startup.cs in older versions), you'll need to configure the Identity services:

builder.Services.AddDbContext<ApplicationDbContext>(options =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));

builder.Services.AddIdentity<ApplicationUser, IdentityRole>(options => options.SignIn.RequireConfirmedAccount = true)
    .AddEntityFrameworkStores<ApplicationDbContext>();

// If using Razor Pages
builder.Services.AddRazorPages();

Core Concepts

Users: Represents the authenticated identity of a person or service.
Roles: Allows you to group users and assign permissions based on those groups.
Claims: Key-value pairs that store additional information about the user.
Stores: Abstract interfaces for persisting user and role data.
Managers: Classes that provide methods for interacting with users and roles (e.g., UserManager, RoleManager).

User Management

Learn how to create, retrieve, update, and delete users. This includes managing user properties, passwords, and email confirmations.

Example of creating a new user:

var user = new ApplicationUser { UserName = "testuser@example.com", Email = "testuser@example.com" };
var result = await _userManager.CreateAsync(user, "Password123!");

if (result.Succeeded)
{
    // User created successfully
}
else
{
    // Handle errors
}

Authentication and Login

This section details how to implement user login and logout functionality using ASP.NET Core's authentication middleware. It covers:

Configuring the authentication middleware.
Implementing sign-in and sign-out actions.
Using SignInManager.

Authorization

Understand how to secure your application's resources using ASP.NET Core Identity's authorization features. This includes role-based and claim-based authorization.

Example of applying authorization attributes:

[Authorize(Roles = "Admin")]
public IActionResult AdminDashboard()
{
    return View();
}

Password Management

Discover how to enforce password policies, such as complexity requirements, minimum length, and lockout strategies. This is crucial for securing your application.

Customizing Identity

ASP.NET Core Identity is highly customizable. Learn how to:

Create custom user and role models.
Implement custom storage providers.
Extend user validation and password policies.

MSDN Documentation