Web API 跨域

1. NuGet下载##

microsoft.aspnet.webapi.cors

2 . Web API 路由中

config.EnableCors(new EnableCorsAttribute());

A.web.config (AB任选其一)

一般浏览器的跨域（写在web.config 的 <system.webServer>下）

 <!--跨域部分设置-->
    <httpProtocol>
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="*" />
        <add name="Access-Control-Allow-Headers" value="Content-Type" />
        <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
      </customHeaders>
    </httpProtocol>
-----------------------------------------------------------

B . Api控制器中(AB任选其一)

		谷歌浏览器跨域，（写在api控制器中）
		/// <summary>
        /// HTTP 200 response with empty body
        /// </summary>
        /// <returns></returns>
        public string Options()
        {
            return null;
        }
-----------------------------------------------------------
		using System.Web.Http.Cors; 

	    [EnableCors(origins: "*", headers: "*", methods: "*")]
	    public class ValuesController : ApiController
	    {  

	    }  

3.api控制器中(2,3任选其一)

//全部通过
config.EnableCors(new EnableCorsAttribute("*", "*", "*"));