js验证时间、ip地址、数字、mac地址函数

js验证时间函数
function check_time(e1)
{
     chkstr=e1.value;
     var pattern="/^(([0-9])|([0][0-9])|([1][0-9])|([2][0-3]))(:([0-5][0-9]))$/"
     eval("var pattern=" + pattern);
     var add_p1 = pattern.test(chkstr);
     return add_p1;
}

function checknull(none) {
    if (none != '') { return false }
    return true
}
js验证数字函数
function checknum(num)
{
var num_length=num.length
var num_letters="1234567890"
    for (p=0; p < num_length; p++)
    {
var num_char = num.charAt(p)
if (num_letters.indexOf(num_char) == -1)
{
     return false
}
    }
    if (num < 1 || num > 10000) { return false }
    return true
}

js验证ip地址函数
function checkip(ip)
{
    var pcount = 0
    var ip_length = ip.length
    var ip_letters = "1234567890."
    for (p=0; p < ip_length; p++)
    {
var ip_char = ip.charAt(p)
if (ip_letters.indexOf(ip_char) == -1)
{
     return false
}
    }
    for (var u = 0; u < ip_length; u++) { (ip.substr(u,1) == ".") ? pcount++ : pcount }
    if(pcount != 3) { return false }
    firstp = ip.indexOf(".")
    lastp = ip.lastIndexOf(".")
    str1 = ip.substring(0,firstp)
    ipstr_tmp = ip.substring(0,lastp)
    secondp = ipstr_tmp.lastIndexOf(".")
    str2 = ipstr_tmp.substring(firstp+1,secondp)
    str3 = ipstr_tmp.substring(secondp+1,lastp)
    str4 = ip.substring(lastp+1,ip_length)
    if (str1 == '' || str2 == '' || str3 == '' || str4 == '') { return false }
    if (str1.length > 3 || str2.length > 3 || str3.length > 3 || str4.length > 3) { return false }
    if (str1 <= 0 || str1 > 255) { return false }
    else if (str2 < 0 || str2 > 255) { return false }
    else if (str3 < 0 || str3 > 255) { return false }
    else if (str4 < 0 || str4 > 255) { return false }
    return true
}

js验证mac地址函数

function check_mac(e1)
{
     chkstr=e1.value;
         var pattern="/^([0-9A-Fa-f]{2})(-[0-9A-Fa-f]{2}){5}|([0-9A-Fa-f]{2})(:[0-9A-Fa-f]{2}){5}/";
     eval("var pattern=" + pattern);
     var add_p1 = pattern.test(chkstr);
  
     if(add_p1==false)
     {
     alert("你输入的MAC地址不正确。");
     }
     return add_p1;
}