<!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="">
</HEAD><BODY>
<script language="JavaScript">
var a="1235sd66";
if(a.search(/[^0-9]/g)!=-1)
{
alert("只能输入数据!");
}
</script>
</BODY>
</HTML>
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
</HEAD><BODY>
<script language="JavaScript">
var a="1235sd66";
if(a.search(/[^0-9]/g)!=-1)
{
alert("只能输入数据!");
}
</script>
</BODY>
</HTML>
方法二:<input name=txt1 onchange="if(/\D/.test(this.value)){alert('只能输入数字');this.value='';}">
方法三:<input onkeyup="if(isNaN(value))execCommand('undo')" onafterpaste="if(isNaN(value))execCommand('undo')">
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<script>
function checkIt(who){
var s=who.T1.value;
var re1=/\D/gi;
if(re1.test(s)){
alert("非法字符");
return false;
}else{
return true;
}
}
</script>
</head><body>
<form onsubmit="return checkIt(this)">
<input type="text" name="T1"><br>
<input type="submit" value="check input">
</form>
</body></html>上面的例子中使用了正则表达式re1=/\D/gi,该正则表达式匹配一个字符串中任何非数字字符,也就是说,一旦s中含有非数字字符,re1的test方法即返回true,否则返回false。