正则。IP验证

function checkIP()                                      //检查IP{var exp=/^(\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])$/; obj=document.getElementById("NTPaddress").value;var reg1 = obj.match(exp); if(reg1==null){alert("NTP地址输入不合法！");return false;}else{//alert("修改成功！");setTimeSet();return true;}}