<script>
function check(str){
return !/[^a-zA-z0-9_.-]/.test(str)
}
alert(check("a-zA-z0-9_.-"));
alert(check("/"));
</script>
function check(str){
return !/[^a-zA-z0-9_.-]/.test(str)
}
alert(check("a-zA-z0-9_.-"));
alert(check("/"));
</script>
var re = /^[a-zA-Z0-9_.-]+$/;
if (re.test(s))
{
//good
}
else
{
//bad
}
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<meta name="GENERATOR" content="Microsoft FrontPage 4.0">
<meta name="ProgId" content="FrontPage.Editor.Document">
<title>请输入下列范围的字符</title>
</head>
<body>
请输入下列范围的字符:a-z、A-Z、1-9、.、*、_
<INPUT type="text" id=text1 name=text1 onblur="if(this.value.match(/[a-zA-Z1-9._]*|/)!=this.value){alert('请输入合法字符!
');this.focus();}">
</body>
</html>