//[EnableCors(origins: "*", headers: "Access-Control-Allow-Origin", methods: "GET,POST,PUT,DELETE,OPTION"
[EnableCors("*", "*", "*")]
public class TestController : ApiController
    {
        public string Post(TestModel text)
        {
            return "Post";
        }
    }

 public static void Register(HttpConfiguration config)
        {
            // Web API 配置和服务
            // Web API 路由
            config.MapHttpAttributeRoutes();
            //config.EnableCors();
            config.EnableCors(new EnableCorsAttribute("*", "*", "*")
            { SupportsCredentials=true });
            
            config.Routes.MapHttpRoute(
                name: "DefaultApi",
                routeTemplate: "api/{controller}/{id}",
                defaults: new { id = RouteParameter.Optional }
            );
        }

function aaa() {
              var aa = $('#aaa').val();
              var bb = $('#bbb').val();

            var testinfo = { "aa": aa, "bb": bb }

            //var your_object = JSON.parse(json_text);
            jQuery.support.cors = true;
            $.ajax({
                url: 'http://localhost:00000/api/Test',
                type: 'POST',
                async: true,
                dataType: "json",                
　　　　　　　　　　//contentType: "application/x-www-form-urlencoded",//键值对传给后端
                contentType: "application/json;charset=utf-8", //json格式传给后端
                //data: { "plantCode": $plantCode, "tempPNs": $txtPN, "dateS": $dateS, "dateE": $dateE },　　　　　　　　　
                data: JSON.stringify(testinfo),
                //data: { a: 'zhangsan' }, 
                success: function (data) {
                    console.log(data),
                    alert('请求成功')
                },
                error: function (xhr) {
                    console.log(),
                    alert('请求失败')
                }
            });
        }