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?...

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I'm creating a component with Vue.js.   When I reference this in any of the the lifecycle hooks (created, mounted, updated, etc.) it evaluates to undefined:  mounted: () => {   console.log(this); // logs "undefined" },     The same t...

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...

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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 have a question concerning how the "this" pointer is treated in a nested function scenario.    Say I insert this following sample code into a web page. I get an error when I call the nested function "doSomeEffects()".  I checked i...