Bug demo：
主页面index.html
<!doctype html><html><head> <title> </title> <meta charset="utf-8" /></head><frameset id="main" cols="200, *" bordercolor="#E8E8FF" framespacing="3" > <frame name="list" src="list.html" scrolling="no"> </frame> <frame name="cont" src="cont.html" > </frame></frameset>
</html>
------------------
子页面1
list.html
<!doctype html><html><head> <title> </title> <meta charset="utf-8" /></head><body><input type="button" value="alert右侧页面变量" onclick="alert(parent.cont.a);" /></body></html>
------------------
子页面2
cont.html
<!doctype html><html><head> <title> </title> <meta charset="utf-8" /> <script type="text/javascript"> var a="hello"; </script></head><body>
</body></html>
主页面index.html
<!doctype html><html><head> <title> </title> <meta charset="utf-8" /></head><frameset id="main" cols="200, *" bordercolor="#E8E8FF" framespacing="3" > <frame name="list" src="list.html" scrolling="no"> </frame> <frame name="cont" src="cont.html" > </frame></frameset>
</html>
------------------
子页面1
list.html
<!doctype html><html><head> <title> </title> <meta charset="utf-8" /></head><body><input type="button" value="alert右侧页面变量" onclick="alert(parent.cont.a);" /></body></html>
------------------
子页面2
cont.html
<!doctype html><html><head> <title> </title> <meta charset="utf-8" /> <script type="text/javascript"> var a="hello"; </script></head><body>
</body></html>
