<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>html－www.51windows.Net</title>
</head>
<body>
以下四个文本框，每个限输入四个字符，输入完后自动跳到下一文本框
<script ID="clientEventHandlersJS" LANGUAGE="javascript">
<!--
function T1_onkeyup() {
if(document.card.T1.value.length==4){
document.card.T2.focus();
}
}
function T2_onkeyup() {
if(document.card.T2.value.length==4){
document.card.T3.focus();
}
}
function T3_onkeyup() {
if(document.card.T3.value.length==4){
document.card.T4.focus();
}
}
//-->
</script>
<form method="POST" name="card" action>
输入字符：
<input type="text" name="T1" size="4" maxlength="4" LANGUAGE="javascript" onkeyup="return T1_onkeyup()">-
<input type="text" name="T2" size="4" maxlength="4" LANGUAGE="javascript" onkeyup="return T2_onkeyup()">-
<input type="text" name="T3" size="4" maxlength="4" LANGUAGE="javascript" onkeyup="return T3_onkeyup()">-
<input type="text" name="T4" size="4" maxlength="4">
</form>
</body>
</html>
<div style="position: absolute; top: 10; right: 10; width: 148; height: 18;cursor:hand">
<input type="button" name="Button" value="查看源代码" onClick= 'window.location = "view-source:" + window.location.href'></div>