文章目录：
此种方法与Jsonp方法类似。是呼叫js文件。通过文件传值。方法如下。
1、在B域(B.com)中建立一个Js文件 JsCreateJson.js。此js返回一个json。代码如下。
{ symbol: 'IBM', price: 91.42 }
2、在A域(A.com)使用CrossByReferenceJs.aspx动态调用此文件。代码如下。
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="CrossByReferenceJs.aspx.cs"
Inherits="IframeTest.CrossByReferenceJs" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd%22>
<html xmlns="http://www.w3.org/1999/xhtml%22>
<head runat="server">
<title></title>
<script type="text/javascript">
function showPrice(data) {
alert("Symbol: " + data.symbol + ", Price: " + data.price);
}
var JSONP = document.createElement("script");
//FF:onload IE:onreadystatechange
JSONP.onload = JSONP.onreadystatechange = function () {
//onreadystatechange，仅IE
if (!this.readyState || this.readyState === "loaded" || this.readyState === "complete") {
JSONP.onload = JSONP.onreadystatechange = null//请内存，防止IE memory leaks
}
}
JSONP.type = "text/javascript";
JSONP.src = "http://b.com/JsCreateJson.js%22";
//在head之后添加js文件
document.getElementsByTagName("head")[0].appendChild(JSONP);
</script>
</head>
<body>
<form id="form1" runat="server">
<div id="demo">
<%--显示调用结果--%>
<input id="Button1" type="button" value="button" onclick="showPrice()" />
</div>
</form>
</body>
</html>
Inherits="IframeTest.CrossByReferenceJs" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd%22>
<html xmlns="http://www.w3.org/1999/xhtml%22>
<head runat="server">
<title></title>
<script type="text/javascript">
function showPrice(data) {
alert("Symbol: " + data.symbol + ", Price: " + data.price);
}
var JSONP = document.createElement("script");
//FF:onload IE:onreadystatechange
JSONP.onload = JSONP.onreadystatechange = function () {
//onreadystatechange，仅IE
if (!this.readyState || this.readyState === "loaded" || this.readyState === "complete") {
JSONP.onload = JSONP.onreadystatechange = null//请内存，防止IE memory leaks
}
}
JSONP.type = "text/javascript";
JSONP.src = "http://b.com/JsCreateJson.js%22";
//在head之后添加js文件
document.getElementsByTagName("head")[0].appendChild(JSONP);
</script>
</head>
<body>
<form id="form1" runat="server">
<div id="demo">
<%--显示调用结果--%>
<input id="Button1" type="button" value="button" onclick="showPrice()" />
</div>
</form>
</body>
</html>