<html>
<head>
<title>leftright</title>
<script language=javascript>
<!--
function form_osSubmit(){
var input_name=document.form1.control1.value;
if(input_name==""){
window.alert("you must enter your name.please");
document.form1.control1.focus();
return false;
} var reg = new RegExp("^[A-Z]","i"); if(!reg.test(input_name)) {
window.alert("must in english,please");
return false;
}}
-->
</script>
</head>
<body>
<form name=form1 onSubmit="form_osSubmit()">
<p><input name=control1></P>
<p><input name=b1 type=submit value="enter"></p>
</form>
</body>
</html>
<head>
<title>leftright</title>
<script language=javascript>
<!--
function form_osSubmit(){
var input_name=document.form1.control1.value;
if(input_name==""){
window.alert("you must enter your name.please");
document.form1.control1.focus();
return false;
} var reg = new RegExp("^[A-Z]","i"); if(!reg.test(input_name)) {
window.alert("must in english,please");
return false;
}}
-->
</script>
</head>
<body>
<form name=form1 onSubmit="form_osSubmit()">
<p><input name=control1></P>
<p><input name=b1 type=submit value="enter"></p>
</form>
</body>
</html>
<head>
<title>leftright</title>
<script language=javascript>
<!--
function form_osSubmit(){
var input_name=document.form1.control1.value;
if(input_name==""){
window.alert("you must enter your name.please");
document.form1.control1.focus();
return false;
} var reg = new RegExp("[^A-Z]","i"); if(reg.test(input_name)) {
window.alert("must in english,please");
return false;
}}
-->
</script>
</head>
<body>
<form name=form1 onSubmit="form_osSubmit()">
<p><input name=control1></P>
<p><input name=b1 type=submit value="enter"></p>
</form>
</body>
</html>
for(var i=0;i>input_name.length;i++)
應該是
for(var i=0;i<input_name.length;i++)
這樣才對而且這個判斷
if(index<0 && index>52)
永遠都不會是TRUE﹐你想這個數小于0又怎么可能大于52呢?應該是
if(index<0 || index>52)還是用樓上兩位的用正則表達式吧﹐處理起來簡單多了