效果查看：http:///keleyi/phtml/divcss/22.htm
html源代碼：
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>用戶登錄html模板-</title>
<script>
function r() {
var username = document.getElementById("username");
var pass = document.getElementById("password");
if (username.value == "") {
alert("請輸入用戶名");
username.focus();
return;
}
if (pass.value == "") {
alert("請輸入密碼");
return;
}
return true;
}
</script>
</head>
<body>
<form>
<table width="350" bgcolor="#ccffcc" border="1">
<tr align=center>
<td>用戶名</td>
<td><input type="text" name="username" id="username"></td>
</tr>
<tr align=center><td>密 碼</td><td><input type="password" name="password" id="password"></td></tr>
<tr align=center><td>驗證碼</td><td><input type="text" name="yanzheng"></td></tr>
<tr align=center><td colspan="2"><input type="button" value="登 錄" onclick="r();" /> <input type="reset" value="重 置" /></td></tr>
</table>
</form>
</body>
</html>