一、子页面是父页面通过window.open弹出的情况
子页面要向父页面传值，只要在document前面加window.opener即可。
如：
1.父页面代码：
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档title>
head>
<script language="javascript">
function tanchu()
{
window.open("Untitled-5.html");
}
script>
<body>
<form id="form1" name="form1" method="post" action="">
<label> <input type="submit" name="button" id="button" value="提交"
onclick="tanchu()" />
label> <label> <input type="text" name="textfield" id="textfield" />
label>
form>
</body>
</html>
2.子页面代码：
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档title>
head>
<script language="javascript">
function aaa()
{
window.opener.document.getElementByIdx('textfield').value='123123123';
}
script>
<body>
<form id="form1" name="form1" method="post" action="">
<label> <input type="submit" name="button" id="button" value="提交"
onclick="aaa()" />
label>
form>
</body>
</html>
二、子页面是iframe框架中的页面情况
子页面要向父页面传值，只要在document前面加parent即可。
1.父页面代码：
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档title>
head>
<body>
<form id="form1" name="form1" method="post" action="">
<label> <input type="text" name="textfield" id="textfield" />
label>
<iframe id="myiframe" src="/UploadFiles/2021-04-02/Untitled-3.html"> form>
</body>
</html>
2.子页面代码
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档title>
head>
<script language="javascript">
function aa()
{
var a=parent.document.getElementByIdx('textfield').value;
alert(a);
}
script>
<body>
<form id="form1" name="form1" method="post" action="">
<label> <input type="submit" name="button" id="button" value="提交"
onClick="aa()" />
label>
form>
</body>
</html>