I have a constructor function which registers an event handler: function MyConstructor(data, transport) { this.data = data; transport.on('data', function () { alert(this.data); }); } // Mock transport object var tran...What's the difference between var A = function () { this.x = function () { //do something }; }; and var A = function () { }; A.prototype.x = function () { //do something };...In a JavaScript file I saw: function Somefunction(){ var that = this; ... } What is the purpose of declaring that and assigning this this to it?...I need to access this from my setInterval handler prefs: null, startup : function() { // init prefs ... this.retrieve_rate(); this.intervalID = setInterval(this.retrieve_rate, this.INTERVAL); }, retrieve_ra...The problem in example 1 is 'this' referring to the global name instead of the myName object. I understand the use of bind() in setting the value of this to a specific object, so it solves the problem in example 1, but why does this proble...
I followed a tutorial for creating a JavaScript stopwatch and am trying to expand it to work with multiple stopwatches (multiple instances of a class). The problem I have is when I am trying to display the current value while the clock is ticking...
I was wondering what the 'this' value (or invocation context) is of the forEach callback function. This code doesn't seem to work: var jow = [5, 10, 45, 67]; jow.forEach(function(v, i, a){ this[i] = v + 1; }); alert(jow); Thx...My question is: function Foo() { this.foo = "bar"; // <- What is "this" here? } From what I can tell it depends on how Foo is used, i.e. as a constructor or as a function. What can this be in different circumstances?...Suppose I have JavaScript code like myClass = function(){ function doSomething(){ alert(this); // this1 } } alert(this); //this2 What those two 'this' objects are refer for??...©2020 All rights reserved.