public class ResponseTimeMiddleware
{
// Name of the Response Header, Custom Headers starts with "X-"
private const string RESPONSE_HEADER_RESPONSE_TIME = "X-Response-Time-ms";
// Handle to the next Middleware in the pipeline
private readonly RequestDelegate _next;
public ResponseTimeMiddleware(RequestDelegate next)
{
_next = next;
}
public Task InvokeAsync(HttpContext context)
{
// Start the Timer using Stopwatch
var watch = new Stopwatch();
watch.Start();
context.Response.OnStarting(() => {
// Stop the timer information and calculate the time
watch.Stop();
var responseTimeForCompleteRequest = watch.ElapsedMilliseconds;
// Add the Response time information in the Response headers.
context.Response.Headers[RESPONSE_HEADER_RESPONSE_TIME] = responseTimeForCompleteRequest.ToString();
return Task.CompletedTask;
});
// Call the next delegate/middleware in the pipeline
return this._next(context);
}
}
- 定义中间件扩展类MyMiddlewareExtensions
using Microsoft.AspNetCore.Builder;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace MyApi.Middleware
{
public static class MyMiddlewareExtensions
{
public static IApplicationBuilder UseMyMiddleware(this IApplicationBuilder builder)
{
return builder.UseMiddleware<ResponseTimeMiddleware>();
}
}
}
- 在Startup中的Configure方法中，注册中间件
public void Configure(IApplicationBuilder app, IHostingEnvironment env,
Microsoft.AspNetCore.Hosting.IApplicationLifetime lifetime)
{
//跨域设置
app.UseCors(builder => builder
.AllowAnyOrigin()
.AllowAnyMethod()
.AllowAnyHeader()
.AllowCredentials());
app.UseHttpsRedirection();
app.UseMyMiddleware();//注册中间件
app.UseMvc();
}