Handling Object arguments

Question

Hi everyone,

I am new to JavaScript OO programming please bear with me for any ambiguities.

I have a method that requires an object as its arguments. The required object sets options for the method to work with.

var objInstance = csvObj.getData({
    url: '', // csv url

    format: '', // return data format

    onComplete: function (output) {
           // a function that will display data returned
    }
});

csvObj is defined below

var csvObj = { 
    getData: function (o) {

        var format = o.format || 'json',  //optional options 
            url = o.url, callback = o.onComplete;   // required options

        function include_js(jsurl) {  // private function for performing cross dormain requests
            var script = document.createElement("script");
            script.type = "text/javascript";

            script.src = jsurl;
            document.getElementsByTagName("head")[0].appendChild(script);
        }


        (function () { // anonymous function for proccessing and returning data

            if (typeof  callback === 'function' && url) {  // if require options are defined

                if (!window.call_back) {    // and global call_back function is not yet defined
                    window.call_back = callback;  // define global call_back function (will be called when external script is loaded)
                }

                var restQuery = 'http://query.yahooapis.com/v1/public/yql?q=',
                query = 'select * from csv where url="' +  url + '" and columns="' + cols + '"', 

                yqlQuery = restQuery + encodeURIComponent(query)  + '&format=' + data + '&callback=call_back'; // create YQL query
                include_js(yqlQuery);  // create a cross dormain YQL request 
            } 
        else {
               alert('onComplete function or csv url not defined.'); // required options not defined
            }
        }());  

    }
};

Question: Is there a better way of handling object arguments than simply accessing like this:

var privateProperty = object.property; or

var privateMethod = object.method;

Answer 1

Your approach is totally valid. You could do it like this, too:

var privateMethod = object['method'];

This can be very handy for dynamically getting properties, but in general i prefer object.method, because it is much easier to read.