javascript - How to push from forEach in prototype to array in constructor? -

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• how access correct `this` inside callback? 6 answers

if have global array this

var arr = [value1, value2...]; 

i got construcotor this

function myfunction() {     this.array = [];     this.toarray(); } 

and prototype method this

myfunction.prototype.toarray = function() {     arr.foreach(function() {         if (statement) {         // how can if here, want push current value, array in cunstructor function?         }     }); } 

as comment says, if comment is, want push current value in foreach function array in constructor function? tried this.array.push(); realized cant use since refers arr array.

edit if don't var = this in snippet above can :

myfunction.prototype.toarray = function(arr) {     arr.foreach((function(item) {         if (item%2 ===0) {            this.array.push(item);         }     }).bind(this)); } 

but prefer :

function myfunction() {      this.array = [];  }    myfunction.prototype.toarray = function(arr) {      arr.foreach((function(item) {          if (item%2 ===0) {             this.array.push(item);          }      }).bind(this));  }    var test = new myfunction();  var arr = [1, 2, 3, 4];  test.toarray(arr);  alert(test.array);