NetCore消息管道 Middleware

中间件定义

/// <summary>
/// 自定义中间件1
/// </summary>
public class MyMiddleware : IMiddleware
{
    public async Task InvokeAsync(HttpContext context, RequestDelegate next)
    {
        Console.WriteLine("MyMiddleware_1,开始处理");
        await next.Invoke(context);
        Console.WriteLine("MyMiddleware_1，结束");
    }
}

/// <summary>
/// 自定义中间件2
/// </summary>
public class MyMiddleware2 : IMiddleware
{
    public async Task InvokeAsync(HttpContext context, RequestDelegate next)
    {
        Console.WriteLine("MyMiddleware_2,开始处理");
        await next.Invoke(context);
        Console.WriteLine("MyMiddleware_2，结束");
    }
}

/// <summary>
/// 通过拓展方法调用
/// </summary>
public static class Middleware2AppBuilderExtensions
{
    public static IApplicationBuilder UseMiddleware2(this IApplicationBuilder app)
    {
        return app.UseMiddleware<MyMiddleware2>();
    }
}

中间件注册

//注入中间件
builder.Services.AddSingleton<MyMiddleware>();
builder.Services.AddSingleton<MyMiddleware2>();

消息管道中加入中间件处理

//UseMiddleware方式调用
app.UseMiddleware<MyMiddleware>();
//拓展方式调用
app.UseMiddleware2();

//Use方式加入处理逻辑到消息管道
app.Use(async (context, next) =>
{
    // await context.Response.WriteAsync("Begin Custom Middleward");
    Console.WriteLine("Begin Custom Middleward");
   await next.Invoke();
    // await context.Response.WriteAsync("End Custom Middleward");
    Console.WriteLine("End Custom Middleward");
});

//Run方式作为处理终结点，不再调用下一个middleward
app.Run(async (context) =>
{
    //await context.Response.WriteAsync("Middleward EndPoint");
    Console.WriteLine("Middleward EndPoint");
});

运行结果