<html> <head> <title>テスト</title> <script> var child = null; function closeChild() { if(child && !child.closed) { child.close(); } } </script> </head> <body> <form method="post" action="http://hoge/foo/bae" target="foo" onsubmit="child = window.open('', this.target)"> <input type="submit" value="開く" /> <input type="button" value="閉じる" onclick="closeChild()" /> </form> </body> </html>