Question

I am storing some JSON data in a text file to query using jQuery Ajax in my page. Currently, my text file contains around 10 facets of data (which could contain an additional 30 facets of data). The JSON data contains a questions and answers to those questions.

In my JavaScript files, I have setup different functions to get specific bits of data.

For example:

function GetAnswer(questionName) {
    var correctAnswer = null;

    jQuery.ajax({
        type: "GET",
        url: "../content/questions.txt",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        data: "",
        async: false,
        success: function (result) {
            $.each(result, function (i, q) {    
                if (q.questionID == questionName) {
                    correctAnswer = q.correctAnswer;
                    return false;
                }
            });
        },
        error: function () {   },
        complete: function () {   }
    });

    return correctAnswer ;
}

As you can see from my code-snippet, I am looping through my JSON to get the data I need. I have other functions coded in a similar fashion to get the question type, question name etc.

What I am finding is that I am calling these functions one after another to get the data I need. I think the way I am querying my JSON data is not good from a performance point-of-view since I am looping through the whole of my JSON dataset until I find a match.

Is there a better way to query my JSON data?

NOTE: I am having to use a text file to store questions due to restrictions of the technology I am using (SCORM 1.2).

Answer 1

Looping through your JSON object is relatively quick. What is slow (comparatively) is loading in that text file each time (though it may be cached).

Either way, I would suggest loading in the JSON either the first time the user initiates a question/answer situation, or just load it in on page load (you can do it asynchronously) and store it for later use.

Example of the latter:

jQuery(document).ready(function(){
    var questions = '';

    jQuery.ajax({
        type: "GET",
        url: "../content/questions.txt",
        contentType: "application/json; charset=utf-8",
        dataType: "json",
        data: "",
        async: false,
        success: function (result) {
            questions = result;
        },
        error: function () {   },
        complete: function () {   }
    });

    function GetAnswer(questionName) {
        var correctAnswer = null;
        $.each(questions, function (i, q) {    
            if (q.questionID == questionName) {
                correctAnswer = q.correctAnswer;
                return false;
            }
        });

        return correctAnswer ;
    }
});