请教大神为何运行之后没反应?
<!DOCTYPE html>
<html>
<head>
<title> new document </title>
<meta http-equiv="Content-Type" content="text/html; charset=gbk"/>
<script type="text/javascript">
function openWindow()
{var mychar=confirm("是否确定点击?");
if(mychar==true)
{var myurl=prompt("请输入你的网址:","http://www.imooc.com/");
if (myurl!=null)
{ window.open(myurl,'_blank','width=400px,height=500px,menubar=no,toolbar=no');}
else
{alert("88");}
else
{alert("88");}
}
</script>
</head>
<body>
<input type="button" value="新窗口打开网站" onclick="openWindow()" />
</body>
</html>