<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
<script type="text/javas
function checkInput(){
var no = document.getElementById('no').value;
alert(no);
var re=/^[-+]?d+(.d+)?$/;
if (no.match(re) == null){
alert("不是数字");
return false;}
else{
alert("就是数字");
return true;
}
}
</script>
</HEAD>
<BODY>
输入验证: <input type="text" id="no" />
<input type="submit" on
</BODY>
</HTML>