求验证ip地址的正则表达式

[bbbb010]

例如用户只能输入192.168.0.15这种格式的ip地址

[liuchuntao]

function checkIp()
{
str=document.form1.txtIP.value;
if(/^(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/.test(str)==false)
{
window.alert('错误的IP地址格式');
document.RegExpDemo.txtIP.select();
document.RegExpDemo.txtIP.focus();
return;
}
if(RegExp.$1<1 || RegExp.$1>254||RegExp.$2<0||RegExp.$2>254||RegExp.$3<0||RegExp.$3>254||RegExp.$4<1||RegExp.$4>254)
{
window.alert('错误的IP地址');
document.RegExpDemo.txtIP.select();
document.RegExpDemo.txtIP.focus();
return;
}
//剔除 如 010.020.020.03 前面 的0
var str=str.replace(/0(\d)/g,"$1");
str=str.replace(/0(\d)/g,"$1");
window.alert(str);
}

[DwNet]

<SCRIPT LANGUAGE="JavaScript">
function isip(s){
var check=function(v){try{return (v<=255 && v>=0)}catch(x){return false}};
var re=s.split(".")
return (re.length==4)?(check(re[0]) && check(re[1]) && check(re[2]) && check(re[3])):false
}

var s="202.197.78.129";
alert(isip(s))
</SCRIPT>

[littleboys]

Expression: ^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$
Rating: 5
Description: This matches an IP address, putting each number in its own group that can be retrieved by number. If you do not care about capturing the numbers, then you can make this shorter by putting everything after ^ until immediately after the first \. in a group ...
Matches: [0.0.0.0], [255.255.255.02], [192.168.0.136] [ More Details]
Non-Matches: [256.1.3.4], [023.44.33.22], [10.57.98.23.]