ASP.NET Core 统一异常处理和返回

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Newtonsoft.Json;
using System;
using System.Net;
using System.Threading.Tasks;

public class ErrorHandlingMiddleware
{
private readonly RequestDelegate next;

public ErrorHandlingMiddleware(RequestDelegate next)
{
this.next = next;
}

public async Task Invoke(HttpContext context)
{
try
{
await next(context);
}
catch (Exception ex)
{
var statusCode = context.Response.StatusCode;
if (ex is ArgumentException)
{
statusCode = 200;
}
await HandleExceptionAsync(context, statusCode, ex.Message);
}
finally
{
var statusCode = context.Response.StatusCode;
var msg = "";
if (statusCode == 401)
{
msg = "未授权";
}
else if (statusCode == 404)
{
msg = "未找到服务";
}
else if (statusCode == 502)
{
msg = "请求错误";
}
else if (statusCode != 200)
{
msg = "未知错误";
}
if (!string.IsNullOrWhiteSpace(msg))
{
await HandleExceptionAsync(context, statusCode, msg);
}
}
}

private static Task HandleExceptionAsync(HttpContext context, int statusCode, string msg)
{
var data = new { code = statusCode.ToString(), is_success = false, msg = msg };
var result = JsonConvert.SerializeObject(new { data = data });
context.Response.ContentType = "application/json;charset=utf-8";
return context.Response.WriteAsync(result);
}
}

public static class ErrorHandlingExtensions
{
public static IApplicationBuilder UseErrorHandling(this IApplicationBuilder builder)
{
return builder.UseMiddleware<ErrorHandlingMiddleware>();
}
}

Startup

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
app.UseErrorHandling();
}