为什么没有弹出对话框？
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>我们互动下</title>
<script type="text/javascript">
function jum(){
var tcdhk=confirm("JS进阶篇")；
if(tcdhk==ture){
document.write("恭喜你进入年薪百万的节奏")；}
else{
document.write("你还是个屌丝。")；}
}
</script>
</head>
<body>
<p id="con">关注JS高级篇</p>
<form>
<input type="button" onclick="jum()" value="点击进入"/>
</form>
</body>
</html>
