# 用类直接创建对象关联到变量

经常是用类的实例，也就是 **new User() ;**然而从没想过 只是 new User ,不调用。今天一看到这个 只new ,不调用觉得好奇怪。这样的结果会是什么。有什么用？从而想到， new 这个关键字到底是什么，从前是知道new 一个实例，是先创建一个对象，把函数里的this指向这个对象，并让函数返回这个对象。

原文地址：<https://juejin.im/post/584e1ac50ce463005c618ca2>


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