Javascript isValid()

I dunno about you, but I love the isValid() function in ColdFusion. Its just an amazing collection of usefulness that I use just about all the time. Recently though, I've found myself really wanting something equivalent for client-side validation, so I put together this bit of Javascript code:

function isValid (type, value) {
    var regex;
    switch (type.toLowerCase()) {
        case 'email':
            regex = /^(("[\w-\s]+")|([\w-]+(?:\.[\w-]+)*)|("[\w-\s]+")([\w-]+(?:\.[\w-]+)*))(@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$)|(@\[?((25[0-5]\.|2[0-4][0-9]\.|1[0-9]{2}\.|[0-9]{1,2}\.))((25[0-5]|2[0-4][0-9]|1[0-9]{2}|[0-9]{1,2})\.){2}(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[0-9]{1,2})\]?$)/i
        case 'telephone':
            regex = /^((\+\d{1,3}(-| )?\(?\d\)?(-| )?\d{1,5})|(\(?\d{2,6}\)?))(-| )?(\d{3,4})(-| )?(\d{4})(( x| ext)\d{1,5}){0,1}$/;
        case 'date':
            regex = /^(?=\d)(?:(?:(?:(?:(?:0?[13578]|1[02])(\/|-|\.)31)\1|(?:(?:0?[1,3-9]|1[0-2])(\/|-|\.)(?:29|30)\2))(?:(?:1[6-9]|[2-9]\d)?\d{2})|(?:0?2(\/|-|\.)29\3(?:(?:(?:1[6-9]|[2-9]\d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00))))|(?:(?:0?[1-9])|(?:1[0-2]))(\/|-|\.)(?:0?[1-9]|1\d|2[0-8])\4(?:(?:1[6-9]|[2-9]\d)?\d{2}))($|\ (?=\d)))?(((0?[1-9]|1[012])(:[0-5]\d){0,2}(\ [AP]M))|([01]\d|2[0-3])(:[0-5]\d){1,2})?$/;
        case 'numeric':
        case 'number':
            regex = /^[\d\.]+$/;
        case 'integer':
            regex = /^\d+$/;
        case 'zipcode':
            regex = /^\d{5}([\-]\d{4})?$/;
    return value.match(regex);

Please note that I take no credit for the regular expressions used in this function. I collected them from various sources, and I would credit the original creator if I could find my list of where I got them.



Jon Hartmann, July 2011

I'm Jon Hartmann and I'm a Javascript fanatic, UX/UI evangelist and former ColdFusion master. I blog about mysterious error messages, user interface design questions, and all things baffling and irksome about programming for the web.

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