ASP.NET MVC 实现跨域请求的两种形式

一、使用jsonp请求

 1         $.ajax({
 2             type: "GET",
 3             url: "http://10.174.1.1/Home/Test?callback=?",
 4             data: { id: "1" },
 5             dataType: "jsonp",
 6             jsonp: "callback",
 7             success: function (data) {
 8                 alert(data);
 9             },
10             error: function (XMLHttpRequest, textStatus, errorThrown) {
11                 alert(errorThrown);
12             }
13         });

 1  //Jsonp跨域访问
 2         [HttpGet]
 3         public ActionResult Test()
 4         {
 5             string vid = Request.QueryString["id"];
 6             string callback = Request["callback"];
 7             return new JsonpResult<object>(Member.FirstOrDefault(u => u.id == id).Name, callback);
 8         }
 9
10
11         public class JsonpResult<T> : ActionResult
12         {
13             public T Obj { get; set; }
14             public string CallbackName { get; set; }
15
16             public JsonpResult(T obj, string callback)
17             {
18                 this.Obj = obj;
19                 this.CallbackName = callback;
20             }
21
22             public override void ExecuteResult(ControllerContext context)
23             {
24                 var js = new System.Web.Script.Serialization.JavaScriptSerializer();
25                 var jsonp = this.CallbackName + "(" + js.Serialize(this.Obj) + ")";
26
27                 context.HttpContext.Response.ContentType = "application/json";
28                 context.HttpContext.Response.Write(jsonp);
29             }
30         }

二、跨域资源共享

相比 JSONP 请求，跨域资源共享要简单许多，也是实现跨域 AJAX 请求的首选。不过在 IE9 还没有对该技术的支持，FireFox 就已经支持了

 1         $.ajax({
 2             type: "GET",
 3             url: "http://10.174.1.1/Home/Test2",
 4             data: { id: "1" },
 5             dataType: "json",
 6             success: function (data) {
 7                 alert(data);
 8             },
 9             error: function (XMLHttpRequest, textStatus, errorThrown) {
10                 alert(errorThrown);
11             }
12         });

1         //跨站资源共享实现跨站AJAX请求
2         public ActionResult Test2()
3         {
4             string vid = Request.QueryString["id"];
5             HttpContext.Response.AppendHeader("Access-Control-Allow-Origin", "*");
6             return Json(Member.FirstOrDefault(u => u.id == id).Name, JsonRequestBehavior.AllowGet);7
8         }