Check Domain Name Validator

Snippet Name: Ultimate domain name validator
Description: This will validate nearly any domain name correctly.

<?
function checkDomain(nname)
{
var arr = new Array(
'.com','.net','.org','.biz','.coop','.info','.museum','.name',
'.pro','.edu','.gov','.int','.mil','.ac','.ad','.ae','.af','.ag',
'.ai','.al','.am','.an','.ao','.aq','.ar','.as','.at','.au','.aw',
'.az','.ba','.bb','.bd','.be','.bf','.bg','.bh','.bi','.bj','.bm',
'.bn','.bo','.br','.bs','.bt','.bv','.bw','.by','.bz','.ca','.cc',
'.cd','.cf','.cg','.ch','.ci','.ck','.cl','.cm','.cn','.co','.cr',
'.cu','.cv','.cx','.cy','.cz','.de','.dj','.dk','.dm','.do','.dz',
'.ec','.ee','.eg','.eh','.er','.es','.et','.fi','.fj','.fk','.fm',
'.fo','.fr','.ga','.gd','.ge','.gf','.gg','.gh','.gi','.gl','.gm',
'.gn','.gp','.gq','.gr','.gs','.gt','.gu','.gv','.gy','.hk','.hm',
'.hn','.hr','.ht','.hu','.id','.ie','.il','.im','.in','.io','.iq',
'.ir','.is','.it','.je','.jm','.jo','.jp','.ke','.kg','.kh','.ki',
'.km','.kn','.kp','.kr','.kw','.ky','.kz','.la','.lb','.lc','.li',
'.lk','.lr','.ls','.lt','.lu','.lv','.ly','.ma','.mc','.md','.mg',
'.mh','.mk','.ml','.mm','.mn','.mo','.mp','.mq','.mr','.ms','.mt',
'.mu','.mv','.mw','.mx','.my','.mz','.na','.nc','.ne','.nf','.ng',
'.ni','.nl','.no','.np','.nr','.nu','.nz','.om','.pa','.pe','.pf',
'.pg','.ph','.pk','.pl','.pm','.pn','.pr','.ps','.pt','.pw','.py',
'.qa','.re','.ro','.rw','.ru','.sa','.sb','.sc','.sd','.se','.sg',
'.sh','.si','.sj','.sk','.sl','.sm','.sn','.so','.sr','.st','.sv',
'.sy','.sz','.tc','.td','.tf','.tg','.th','.tj','.tk','.tm','.tn',
'.to','.tp','.tr','.tt','.tv','.tw','.tz','.ua','.ug','.uk','.um',
'.us','.uy','.uz','.va','.vc','.ve','.vg','.vi','.vn','.vu','.ws',
'.wf','.ye','.yt','.yu','.za','.zm','.zw');
 
var mai = nname;
var val = true;
 
var dot = mai.lastIndexOf(".");
var dname = mai.substring(0,dot);
var ext = mai.substring(dot,mai.length);
//alert(ext);
 
if(dot>2 && dot<57)
{
     for(var i=0; i<arr.length; i++)
     {
       if(ext == arr[i])
       {
           val = true;
          break;
       }     
       else
       {
           val = false;
       }
     }
     if(val == false)
     {
             alert("The domain extension "+ext+" is incorrect or unknown.");
           return false;
     }
     else
     {
          for(var j=0; j<dname.length; j++)
          {
            var dh = dname.charAt(j);
            var hh = dh.charCodeAt(0);
            if((hh > 47 && hh<59) || (hh > 64 && hh<91) || (hh > 96 && hh<123) || hh==45 || hh==46)
            {
                if((j==0 || j==dname.length-1) && hh == 45)     
                  {
                        alert("The domain name cannot begin or end with '-'");
                     return false;
                 }
            }
          else     {
                  alert("Your domain name cannot contain any special characters.");
                return false;
            }
          }
     }
}
else
{
 alert("The domain name entered is either too short or too long");
 return false;
}     
 
return true;
}

?>