场景：由于业务需求，需要在一个页面显示另外一个页面，并且右键查看源代码看不到一条链接。
实现方式：使用iframe来显示这个首页，至于首页的地址则使用jQuery Ajax来获取。html代码如下：
<html> <head> <title></title> <script src=""https://ajax.aspnetcdn.com/ajax/jquery/jquery-1.7.2.min.js"" type=""text/javascript""></script> <style type=""text/css""> body { overflow-x:hidden; overflow-y:hidden;} html, body, iframe { width:100%; height:100%; margin:0px; padding:0px;} </style> <script type=""text/javascript""> $(function(){ $.ajax({ url: """ + iisUrl + @"/Ajax/SnapsHijackService.ashx"", type: ‘POST‘, dataType: ‘json‘, data:{ releaseId: " + releaseId + @" }, success: function(data) { var url = $.trim(decodeURIComponent(data.url)); $(""#iframe"").attr(""src"",url); }, error:function(data){ alert(data); console.log(data.url); } }); }); </script> </head> <body> <iframe id=""iframe"" frameborder=‘no‘></iframe> </body> </html>
SnapsHijackService.ashx代码如下：
string sql = "select user_site_url from t_synth_release_site where id = " + releaseId; string url = string.Empty; System.Data.DataTable dtUrl = NetWin.SnapsHijack.Common.Helper.MysqlHelper.Select(sql); if (dtUrl == null || dtUrl.Rows.Count == 0) { log.Write("读取广告计划：" + releaseId + "的官网代码失败。sql：" + sql); return; } url = dtUrl.Rows[0]["user_site_url"].ToString().ToLower(); if (!url.StartsWith("http")) { url = "http://" + url; log.Write("广告计划网址：" + url); } string result = "{\"url\":\"" + UrlEncode(url) + "\"}"; context.Response.Write(result); context.Response.End();
出现的问题：由于业务需求，需要在别的站点通过反向代理的方式来请求这个一般处理程序，如此就会因为js的同源策略导致获取url失败。
解决方案一：只需要在一般处理程序那里添加一句话即可解决问题。此法在IE9中无效。在FireFox、Chrome中可行。
... string result = "{\"url\":\"" + UrlEncode(url) + "\"}"; context.Response.AddHeader("Access-Control-Allow-Origin", "*"); context.Response.Write(result); context.Response.End();
解决方案二：修改ajax的返回类型。具体看代码：
<html> <head> <title></title> <script src=""https://ajax.aspnetcdn.com/ajax/jquery/jquery-1.7.2.min.js"" type=""text/javascript""></script> <style type=""text/css""> body { overflow-x:hidden; overflow-y:hidden;} html, body, iframe { width:100%; height:100%; margin:0px; padding:0px;} </style> <script type=""text/javascript""> $(function(){ $.ajax({ url: """ + iisUrl + @"/Ajax/SnapsHijackService.ashx"", type: ‘get‘, dataType: ""jsonp"", jsonp: ""callbackparam"", jsonpCallback:""jsonpCallback1"", data:{ releaseId: " + releaseId + @" }, success: function(data) { var url = $.trim(decodeURIComponent(data[0].url)); $(""#iframe"").attr(""src"",url); }, error:function(data){ alert(""error""); } }); }); </script> </head> <body> <iframe id=""iframe"" frameborder=‘no‘></iframe> </body> </html>
一般处理程序：
string sql = "select user_site_url from t_synth_release_site where id = " + releaseId; string url = string.Empty; System.Data.DataTable dtUrl = Common.Helper.MysqlHelper.Select(sql); if (dtUrl == null || dtUrl.Rows.Count == 0) { log.Write("读取广告计划：" + releaseId + "的官网代码失败。sql：" + sql); return; } url = dtUrl.Rows[0]["user_site_url"].ToString().ToLower(); if (!url.StartsWith("http")) { url = "http://" + url; log.Write("广告计划网址：" + url); } string callbackFunName = context.Request["callbackparam"]; string result = callbackFunName + "([{\"url\":\"" + UrlEncode(url) + "\"}])"; //context.Response.AddHeader("Access-Control-Allow-Origin", "*"); context.Response.Write(result); context.Response.End();
如此，IE、FireFox、Chrome就都可以了。ajax请求的链接为：http://wuzhoumh.paiming.net/Ajax/SnapsHijackService.ashx?callbackparam=jsonpCallback1&releaseId=988&_=1487146317414
参考文档：http://www.cnblogs.com/mahatmasmile/archive/2013/03/29/2989505.html
原文：http://www.cnblogs.com/wangwust/p/6401760.html