Why is my variable undefined inside the Underscore.js each function?

Question

Here is my code:

TextClass = function () {
    this._textArr = {};
};

TextClass.prototype = {
    SetTexts: function (texts) {
        for (var i = 0; i < te         


        

Answer 1

this in javascript does not work the same way as you would expect. read this article: http://www.digital-web.com/articles/scope_in_javascript/

short version:

the value of this changes every time you call a function. to fix, set another variable equal to this and reference that instead

TextClass = function () {
    this._textArr = {};
};

TextClass.prototype = {
    SetTexts: function (texts) {
        var that = this;
        for (var i = 0; i < texts.length; i++) {
            that._textArr[texts[i].Key] = texts[i].Value;
        }
    },
    GetText: function (key) {
        var value = this._textArr[key];
        return String.IsNullOrEmpty(value) ? 'N/A' : value;
    }
};