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jQuery validate: How to add a rule for regular expression validation?

Asked 2008-11-11T12:34:29.607
258

I am using the jQuery validation plugin. Great stuff! I want to migrate my existing ASP.NET solution to use jQuery instead of the ASP.NET validators. I am missing a replacement for the regular expression validator. I want to be able to do something like this:

$("Textbox").rules("add", { regularExpression: "^[a-zA-Z'.\s]{1,40}$" })

How do I add a custom rule to achieve this?

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2 Answers

85

You can use the addMethod()

e.g

$.validator.addMethod('postalCode', function (value) { 
    return /^((\d{5}-\d{4})|(\d{5})|([A-Z]\d[A-Z]\s\d[A-Z]\d))$/.test(value); 
}, 'Please enter a valid US or Canadian postal code.');

good article here https://web.archive.org/web/20130609222116/http://www.randallmorey.com/blog/2008/mar/16/extending-jquery-form-validation-plugin/

answered 2008-11-11T14:01:39.243
25

Extending PeterTheNiceGuy's answer a bit:

$.validator.addMethod(
        "regex",
        function(value, element, regexp) {
            if (regexp.constructor != RegExp)
                regexp = new RegExp(regexp);
            else if (regexp.global)
                regexp.lastIndex = 0;
            return this.optional(element) || regexp.test(value);
        },
        "Please check your input."
);

This would allow you to pass a regex object to the rule.

$("Textbox").rules("add", { regex: /^[a-zA-Z'.\s]{1,40}$/ });

Resetting the lastIndex property is necessary when the g-flag is set on the RegExp object. Otherwise it would start validating from the position of the last match with that regex, even if the subject string is different.

Some other ideas I had was be to enable you use arrays of regex's, and another rule for the negation of regex's:

$("password").rules("add", {
    regex: [
        /^[a-zA-Z'.\s]{8,40}$/,
        /^.*[a-z].*$/,
        /^.*[A-Z].*$/,
        /^.*[0-9].*$/
    ],
    '!regex': /password|123/
});

But implementing those would maybe be too much.

answered 2009-05-09T16:40:21.300

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