.Net Core 3.1 CORS跨域处理

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.net core3.1 CORS跨域处理

** .net core3.1是一个LTS版本，这里我们新建一个core3.1的API项目，目录结构如下： 这里序列化使用了Newtonsoft.Json UserController.cs

using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Mvc; using Newtonsoft.Json; using test.Models; namespace test.Controllers { [ApiController] [Route("[controller]")] public class UserController : Controller { [HttpGet] public ContentResult Index() { List<User> users = new List<User>(); users.Add(new User(1, "测试1", 28, "男")); users.Add(new User(2, "测试2", 25, "女")); users.Add(new User(3, "测试3", 22, "女")); List<Order> orders = new List<Order>(); orders.Add(new Order(0001,"电脑")); orders.Add(new Order(0002, "手机")); Hashtable result = new Hashtable(); result.Add("user", users); result.Add("order", orders); return Content(JsonConvert.SerializeObject(result)); } } }

Order.cs

using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; namespace test.Models { public class Order { public int OrderId { get; set; } public string Product { get; set; } public Order(int OrderId, string Product) { this.OrderId = OrderId; this.Product = Product; } } }

User.cs

using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; namespace test.Models { public class User { public int Id { get; set; } public string Name { get; set; } public int Age { get; set; } public string Gender { get; set; } public User(int Id, string Name, int Age, string Gender) { this.Id = Id; this.Name = Name; this.Age = Age; this.Gender = Gender; } } }

实现跨域需要修改Program.cs和Startup.cs两个文件 Program.cs

using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Hosting; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.Hosting; using Microsoft.Extensions.Logging; namespace test { public class Program { public static void Main(string[] args) { CreateHostBuilder(args).Build().Run(); } public static IHostBuilder CreateHostBuilder(string[] args) => Host.CreateDefaultBuilder(args) .ConfigureWebHostDefaults(webBuilder => { webBuilder.UseStartup<Startup>(). //使用*可以在URL用IP访问，默认使用localhost UseUrls("http://*:5000;https://*:5001"); }); } }

Startup.cs

using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using Microsoft.AspNetCore.Builder; using Microsoft.AspNetCore.Hosting; using Microsoft.AspNetCore.HttpsPolicy; using Microsoft.AspNetCore.Mvc; using Microsoft.Extensions.Configuration; using Microsoft.Extensions.DependencyInjection; using Microsoft.Extensions.Hosting; using Microsoft.Extensions.Logging; namespace test { public class Startup { public Startup(IConfiguration configuration) { Configuration = configuration; } public IConfiguration Configuration { get; } // This method gets called by the runtime. Use this method to add services to the container. public void ConfigureServices(IServiceCollection services) { services.AddControllers(); //跨域设置 services.AddCors(options => { options.AddPolicy("any", builder => { builder.WithOrigins("*"); }); }); } // 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(); //跨域配置，app.UseCors()需要置于app.UseRouting()和app.UseEndpoints之间 app.UseCors("any"); app.UseAuthorization(); app.UseEndpoints(endpoints => { endpoints.MapControllers(); }); } } }

这里我们使用Kestrel启动 用PostMan测试https://主机的IP:5001/User显示实现了跨域处理：