本文通過舉例，由淺入深的講解了解決js函數閉包內存泄露問題的辦法，分享給大家供大家參考，具體內容如下
原始代碼：
function Cars(){ this.name = "Benz"; this.color = ["white","black"];}Cars.prototype.sayColor = function(){ var outer = this; return function(){ return outer.color };};var instance = new Cars();console.log(instance.sayColor()())優化后的代碼：
function Cars(){ this.name = "Benz"; this.color = ["white","black"];}Cars.prototype.sayColor = function(){ var outerColor = this.color; //保存一個副本到變量中 return function(){ return outerColor; //應用這個副本 }; outColor = null; //釋放內存};var instance = new Cars();console.log(instance.sayColor()())稍微復雜一點的例子：
function inheritPrototype(subType,superType){ var prototype = Object(superType.prototype); prototype.constructor = subType; subType.prototype = prototype;}function Cars(){ this.name = "Benz"; this.color = ["white","black"];}Cars.prototype.sayColor = function(){ var outer = this; return function(){ return outer.color; };};function Car(){ Cars.call(this); this.number = [321,32];}inheritPrototype(Car,Cars);Car.prototype.sayNumber = function(){ var outer = this; return function(){ return function(){ return outer.number[outer.number.length - 1]; } };};var instance = new Car();console.log(instance.sayNumber()()());首先，該例子組合使用了構造函數模式和原型模式創建Cars 對象，并用了寄生組合式繼承模式來創建Car 對象并從Cars 對象獲得屬性和方法的繼承；
其次，建立一個名為instance 的Car 對象的實例；instance 實例包含了sayColor 和sayNumber 兩種方法；
最后，兩種方法中，前者使用了一個閉包，后者使用了兩個閉包，并對其this 進行修改使其能夠訪問到this.color 和this.number。
這里存在內存泄露問題，優化后的代碼如下：
function inheritPrototype(subType,superType){ var prototype = Object(superType.prototype); prototype.constructor = subType; subType.prototype = prototype;}function Cars(){ this.name = "Benz"; this.color = ["white","black"];}Cars.prototype.sayColor = function(){ var outerColor = this.color; //這里 return function(){ return outerColor; //這里 }; this = null; //這里};function Car(){ Cars.call(this); this.number = [321,32];}inheritPrototype(Car,Cars);Car.prototype.sayNumber = function(){ var outerNumber = this.number; //這里 return function(){ return function(){ return outerNumber[outerNumber.length - 1]; //這里 } }; this = null; //這里};var instance = new Car();console.log(instance.sayNumber()()());以上就是為大家分享的解決方法，希望對大家的學習有所幫助。
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