CORS策略已阻止从来源“ http：// localhost：4200”访问“ http：// localhost：25776 / api / Upload”处的XMLHttpRequest

问题描述

我正在http://localhost:4200上运行angular spa应用程序，并在http://localhost:25667上运行.net core 3应用程序。

当我的角度SPA不断收到以下错误消息时。

Access to XMLHttpRequest at 'http://localhost:25776/api/Upload' from origin 'http://localhost:4200' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

即使我认为我的CORS配置正确。

这是我的startup.cs文件。

public void ConfigureServices(IServiceCollection services)
        {
            services.AddCors(options =>
            {
                options.AddPolicy(
                    name: "CorsPolicy",builder => builder.WithOrigins("http://localhost:4200/")
                    .AllowAnyHeader()
                    .AllowAnyMethod()
                    .AllowCredentials()
                    .SetIsOriginAllowed((host) => true));
            });

            services.AddHttpContextAccessor();

            services.AddControllers().AddNewtonsoftJson();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app,IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseHttpsRedirection();

            app.UseRouting();

            app.UseCors("CorsPolicy");

 

            app.UseAuthorization();


            app.UseDefaultFiles();
            app.UseStaticFiles(new StaticFileOptions()
            {
                FileProvider = new PhysicalFileProvider(Path.Combine(Directory.GetCurrentDirectory(),@"Upload")),RequestPath = new PathString("/Upload")
            });

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
                endpoints.MapFallbackToController("Index","Fallback");
            });
        }

这是我的控制器文件

using System.Collections.Generic;
using Microsoft.AspNetCore.Cors;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using TestApp.API.Models;
using TestApp.API.Services;
namespace TestApp.API.Controllers
{
    [ApiController]
    [Route("api/[controller]")]
    [EnableCors("CorsPolicy")]
    public class UploadController : ControllerBase
    {
        // GET api/value
        [HttpGet]
        public IEnumerable<Upload> GetTempuploadData()
        {
            UploadServices uploadServices = new UploadServices();
            return uploadServices.GetTempuploadData();

        }
    }
}

我还安装了 Microsoft.AspNetCore.Cors nuget软件包。

任何帮助将不胜感激。

谢谢。

解决方法

您需要在/中删除此WithOrigins。

services.AddCors(options =>
        {
            options.AddPolicy(
                name: "CorsPolicy",builder => builder.WithOrigins("http://localhost:4200")
                .AllowAnyHeader()
                .AllowAnyMethod()
                .AllowCredentials()
                .SetIsOriginAllowed((host) => true));
        });

,

我正在发布我的解决方案，以防有人遇到类似问题。

问题与我的API中的launchSetting.json文件有关。 我将anonymousAuthentication设置为true，它解决了这个问题。与CORS设置无关。

  "iisSettings": {
    "windowsAuthentication": true,"anonymousAuthentication": true,"iisExpress": {
      "applicationUrl": "http://localhost:25776/","sslPort": 0
    }