这次要实现一个window.open打开子视窗的同时传参数到子视窗，关闭的时候返回参数。
当然简单的做法非常简单，直接在window.open的URL之后接参数即可，但是毕竟get method的参数长度受浏览器的限制，一般从2KB到8KB。
除了get之外，还可以用window.postMessage(), 参考下面的case演示。
主视窗HTML如下：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script src="js/jquery-3.1.1.min.js" type="text/javascript"></script>
<script type="text/javascript"> function openWin() {
var params = new Array();
params[0] = new Array("CL1", "milo test");
params[1] = new Array("CL2", "Taipei"); var popupwin = window.open("popup.jsp", "Map", "status=0,title=0,height=600,width=800,scrollbars=1");
//onload只能执行一次，也就是如果子窗口有onload事件，可能会覆盖。
popupwin.onload = function(e){
popupwin.postMessage(params, "http://"+window.location.host);
}
popupwin.onunload = function(e){
var val = popupwin.returnValue;
alert(val);
}
} </script>
</head>
<body>
<input type="button" value="Open Window" onclick="openWin()" />
</body>
</html>
打开子视窗之后，要给视窗传参数params，并在子视窗上显示出参数值。
但前提是子视窗必须已经完成监听事件message的填加，否则onload的时候参数传过去也收不到。为了解决这个问题，子视窗必须要在onload事件执行之前添加message事件监听。这里我是添加document.onreadystatechange事件，先看看html的document.readyState, 总的有五个取值：
- uninitialized – Has not started loading yet
- loading – Is loading
- loaded – Has been loaded
- interactive – Has loaded enough and the user can interact with it
- complete – Fully loaded
为了在onload被fired之前且安全的添加window事件，这里选择用complete，DOC全部加载完且还未触发onload。
子视窗参考如下：
<!–
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco; color: #3933ff}
p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco; color: #932192}
p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco; color: #009193}
p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco; color: #4e9192}
p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco}
p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco; color: #4e9072}
span.s1 {color: #cc7450}
span.s2 {color: #000000}
span.s3 {color: #4e9192}
span.s4 {color: #932192}
span.s5 {color: #3933ff}
span.s6 {color: #929292}
span.s7 {color: #4e9072}
span.s8 {color: #009193}
span.s9 {text-decoration: underline}
span.s10 {color: #931a68}
span.Apple-tab-span {white-space:pre}
–>
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>popup window</title>
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
<script language="javascript" type="text/javascript">
function closeWin() {
window.returnValue = true;
window.close();
}
//HTML DOM fully loaded, and fired window.onload later.
document.onreadystatechange = function(e)
{
if (document.readyState === 'complete')
{
window.addEventListener('message', function(e){
var params = e.data;
$('#cl1').text(params[0][1]);
$('#cl2').text(params[1][1]);
});
}
};
</script>
</head>
<body>
Parameter CL1: <b id="cl1"></b>
Parameter CL2: <b id="cl2"></b>
<div><input type="button" value="Return Value" onclick="closeWin()" /></div>
</body>
</html>
运行结果：
<!–
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Monaco}
–>
