JavaScript regular expression validation for domain name?

Question

How to check a valid domain name and username with regular expression in JavaScript?

function validate()
{
    var         


        

Answer 1

function CheckIsValidDomain(domain) { 
    var re = new RegExp(/^((?:(?:(?:\w[\.\-\+]?)*)\w)+)((?:(?:(?:\w[\.\-\+]?){0,62})\w)+)\.(\w{2,6})$/); 
    return domain.match(re);
} 

try this its work for me.