请大神看看这段代码的异常
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>trick</title>
<script type="text/javascript">
function tanchuang()
{
var i
for(i=0;i>=0;i++)
alert("哈哈哈,你上当啦!!!")
}
</script>
</head>
<body>
<form>
<input type="button" value="点击有奖" onclick="tanchuang()">
</form>
</body>
</html>