CODEWITHSUNDEEP
javascriptjquery
Titan
Titan

Reputation: 6070

Checking function exists from within jQuery plugin

I am rolling my own jQuery form validator for a project I'm working on. I am defining the type of validation required in data-validate on the input elements.

I want to check if this validation function exists in my plugin before calling it (all within the plugin itself).

Before I have used:

if($.isFunction(window['functionName']))
    window['functionName']();

however this doesn't appear to work within my plugin:

(function( $ ) {
    $.fn.validateForm = function(options) {

        ...

        findInputs();

        function validateRequired(input) {

        }

        function findInputs() {

            ...

            if($(this).attr("data-validate"))
            {
                // Get list of required validation functions
                var toValidate = $(this).attr("data-validate").split(/\s+/);

                for(var i = 0; i < toValidate.length; i++) {
                    // Hardcoded function name call for testing
                    if($.isFunction(window['validateRequired']))
                        window['validateRequired']();
                }
            }
        }
    }

Upvotes: 1

Views: 158

Answers (2)

ndg
ndg

Reputation: 2645

The best way to handle this is to declare your functions as part of an object literal. That way, you can reference the literal within your plugin, like so:

(function( $ ) {
    var methods = {
        validateRequired: function(input)
        {
            // STUB
        }
    };

    $.fn.validateForm = function(options) {
        function findInputs() {

            if($.isFunction(methods['validateRequired'])) methods['validateRequired']();

        }
    };
});

Upvotes: 1

Kamil
Kamil

Reputation: 13941

Im not JS expert, but try this:

if(typeof (someFunction) == 'function') {
// do something
}

EDIT

Or like this, using function name as string:

if(typeof this["functionName"] == "function") {
     this["functionName"](); //it exists, call it
 }

I found this here:

javascript: how to judge a function name exists? / see Nick Craver answer.

by googling like this: "function name exists javascript"

If you are searching for something about jQuery - try to search it with javascript keyword instead of jQuery. jQuery is a framework written in javascript.

Upvotes: 0

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