为什么这个我点击注册后没有效果呢？
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content = "text;html;charset=gbk">
<title>注册</title>
<script language="javascript" type="">
function LoginSubmit(){
var name = document.Sign.name.value;
var password = document.Sign.password.value;
var enpass = document.Sign.Ensurepassword.value;
if(name==null||name==""||password==null||password==""||enpass==null||enpass==""){
alter("用户名或密码或确认密码不能为空!");
}
else if(password==enpass){
alter("两次输入密码不一致请重新输入！");
} else{
document.Sign.submit();
}
}
</script>
<style type="text/css">
body{
background-image:url(ba.jpg); }
</style>
</head>
<body>
<form method ="POST" name ="Sign" action="SignIn">
<p align = "left">用 户 名(必填):
<input type="text" name ="name" value="" size="20"></p>
<p allign = "left">密 码(必填):
<input type="password" name="password" value="" size="20"></p>
<p align = "left">确认密码(必填):
<input type="password" name="Ensurepassword" value="" size="20"></p>
<p align = "left">性 别 :
<input type="text" name="sex" value="" size="20"></p>
<p align = "left">性 别 :
<input type="text" name="sex" value="" size="20"></p>
<p align = "left">住 址 :
<input type="text" name="address" value="" size="20"></p>
<p align = "left">联系电话:
<input type="text" name="tel" value="" size="20"></p>
<p align="left">
<input type="button" value="注册" name="sure" onclick="LoginSubmit()">
<input type="reset" value="重置" name="reset" >
</p>
</form>
</body>
</html>
