Entity Framework Core 基础 (1)

创建上下文和模型

安装包

Install-Package Microsoft.EntityFrameworkCore.Sqlite
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添加模型

Blog.cs :

public class Blog
{
    public int Id { get; set; }
    public string Url { get; set; }
    public List<Post> Posts { get; } = new();
}
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Post.cs :

public class Post
{
    public int Id { get; set; }
    public string Title { get; set; }
    public string Content { get; set; }

    public int BlogId { get; set; }
    public Blog Blog { get; set; }
}
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添加上下文

AppDbContext.cs

public class AppDbContext : DbContext
{
    public DbSet<Blog> Blogs { get; set; }
    public DbSet<Post> Posts { get; set; }
    public AppDbContext(DbContextOptions<AppDbContext> options) : base(options)
    {
    }
}
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添加服务配置类

Dependencies.cs

public static class Dependencies
{
    public static void ConfigureServices(IConfiguration configuration, IServiceCollection services)
    {
        services.AddDbContext<AppDbContext>(options => options.UseSqlite(configuration.GetConnectionString("SQLite")));
    }
}
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注入到程序并添加数据库连接配置

Program.cs

Dependencies.ConfigureServices(builder.Configuration, builder.Services);
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appsettings.json

"ConnectionStrings": {
    "SQLite": "Data Source = blogging.db"
}
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使用迁移创建数据库

Install-Package Microsoft.EntityFrameworkCore.Tools
Add-Migration InitialCreate
Update-Database
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参考

Entity Framework Core 概述 - EF Core | Microsoft Learn