跨域请求ajax jsonp的使用解惑

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml" >
 3 <head>
 4     <title>Untitled Page</title>
 5      <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
 6      <script type="text/javascript">
 7     jQuery(document).ready(function(){
 8         $.ajax({
 9             type : "get",
10             async:false,
11             url : "ajax.ashx",
12             dataType : "jsonp",
13             jsonp: "callbackparam",//传递给请求处理程序或页面的,用以获得jsonp回调函数名的参数名(默认为:callback)
14             jsonpCallback:"success_jsonpCallback",//自定义的jsonp回调函数名称,默认为jQuery自动生成的随机函数名
15             success : function(json){
16                 alert(json);
17                 alert(json[0].name);
18             },
19             error:function(){
20                 alert('fail');
21             }
22         });
23         var a="firstName Brett";
24         alert(a);
25     });
26     </script>
27     </head>
28  <body>
29  </body>
30 </html>
<%@ WebHandler Language="C#" Class="ajax" %>
 2 
 3 using System;
 4 using System.Web;
 5 
 6 public class ajax : IHttpHandler {
 7     
 8     public void ProcessRequest (HttpContext context) {
 9         context.Response.ContentType = "text/plain";
10         string callbackFunName = context.Request["callbackparam"];
11         context.Response.Write(callbackFunName + "([ { name:"John"} ] )");
12     }
13  
14     public bool IsReusable {
15         get {
16             return false;
17         }
18     }
19 
20 }
原文地址:https://www.cnblogs.com/B-bowen/p/4310460.html