Introduction détaillée aux problèmes de fermeture

Je rencontre souvent des questions sur les fermetures lors des entretiens

<span style="font-size: 15px; font-family: 宋体"><code class="lang-javascript"><span class="hljs-keyword">var name = <span class="hljs-string">"The Window";   
<span class="hljs-keyword">var object = {
    name : <span class="hljs-string">"My Object",   
    getNameFunc : <span class="hljs-function"><span class="hljs-keyword">function<span class="hljs-params">(){   <span class="hljs-keyword">return <span class="hljs-function"><span class="hljs-keyword">function<span class="hljs-params">(){   <span class="hljs-keyword">return <span class="hljs-keyword">this.name;   
        };   
    },

    getName:<span class="hljs-function"><span class="hljs-keyword">function<span class="hljs-params">(){
        alert(<span class="hljs-keyword">this.name);
    }   
};   
alert(object.getNameFunc()());  <span class="hljs-comment">//The Window
object.getName();  <span class="hljs-comment">//My Object<br/></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></code></span>

Solution au problème de fuite de mémoire de la méthode de fermeture des fonctions js

function Cars(){
  this.name = "Benz";
  this.color = ["white","black"];
}
Cars.prototype.sayColor = function(){
  var outer = this.color; //保存一个副本到变量中

<span style="font-size: 15px"> return function(){ </span><br/><span style="font-size: 15px">return outer//应用这个副本</span>

};

outer = null; //释放内存

<span style="font-size: 15px">};<br/> var instance = new Cars(); <br/>console.log(instance.sayColor()())</span>

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