what's wrong with my javascript scope

This question already has an answer here:

Javascript “this” pointer within nested function 7 answers

---

Either store a reference to this in the enclosing function and use that:

var me = this;
this.suits.forEach(function(currentSuit) {
    console.log(me.suits);
});

Or use bind :

this.suits.forEach(function(currentSuit) {
    console.log(this.suits);
}.bind(this));

Or use the second argument to forEach : (This is probably the best solution.)

this.suits.forEach(function(currentSuit) {
    console.log(this.suits);
}, this);

---

你检查它是这样的（？）：

 $this = this;
 this.suits.forEach(function(currentSuit){

    var scope = $this;

    console.log(scope);

});

---

首先将参考变量保存到甲板作用域中...

function Deck(){
    var self = this; // save a reference to the deck context

    this.suits = [ // this is an array now
        {
            'suit': 'diamonds',
            'symbol': '♦',
            'color': 'red'
        }

    ]; // close suits

    this.cardValues = [
        {
            'name': 'ace',
            'face': 'A',
            'value': 1
        }
    ]; // close cardValues

    this.cards = [];

    console.log(this);

    this.suits.forEach(function(currentSuit){

        var scope = self;

        console.log(scope);

      // scope doesn't work.
      // obviously, scope references window
      // so how do i get it to refer to the deck like it's supposed to.
      // i looked into using call and apply, and even though the concepts 
      // made sense i couldn't figure it out.
      // fuck this is frustrating!

    });
}

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