An unexpected dilemma within a function's scope

I seem to be encountering a problem related to the scope of a variable. The first two instances return the correct value, however, when I subscribe to an event (which appears to be functioning properly), it returns this._id as undefined. I have also attempted using MyFunction._id;

 var i = 0;

 var func = new MyFunction();
 func.init();

 function MyFunction(i){
     this._id = i;
 }

 MyFunction.prototype.init = function(){

     Debugger.log("A : " + this._id); //displays the result of i
     this.myTest; //displays the result of i
     Event.subscribe("UPDATE", this.myTest);// is undefined
 }

 MyFunction.prototype.myTest = function(){
     Debugger.log("B : " + this._id);
 }

Thank you.

Answer №1

Your task is to:

 Event.subscribe("UPDATE", this.myTest.bind(this));

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