javascript – 浏览器和节点之间有什么区别？

浏览器和节点之间有什么区别？例如：

节点上的setName.js：

var setName;
setName = function (name) {
    return this.name = name;
};
setName("LuLu");
//LuLu
console.log(name);
//undefined
console.log(this.name);

浏览器中的setName.html：

<script>
    var setName;
    setName = function (name) {
        return this.name = name;
    };
    setName("LuLu");
    //LuLu
    console.log(name);
    //LuLu
    console.log(this.name);
</script>

第二个日志不同,为什么？

解决方法

Node是JavaScript引擎,而不是浏览器.您在Node中看到未定义的特定原因,以及浏览器中的Lulu？ Differences in the global namespace：

In browsers,the top-level scope is the global scope. That means that in browsers if you’re in the global scope var something will define a global variable. In Node this is different. The top-level scope is not the global scope; var something inside a Node module will be local to that module.

在浏览器中,这是对窗口对象(浏览器的全局命名空间)的引用,用于所有未附加到对象的函数(例如,不像foo.bar()).在Node中,这不是对全局命名空间的引用.

注：节点解释器中的console.log(this.name)将打印Lulu,而不是未定义.那是因为,仅在REPL中,

> this === global
true

进一步阅读@ How To Node: What is “this?”

好的,还有一个编辑按照@Šime Vidas’关于this this的评论提示：

In the global context (outside of any function),this refers to the global object,whether in strict mode or not.

When the this keyword occurs inside a function,its value depends on 07005.

When a function is called as a method of an object,its this is set to the object the method is called on.

更有趣的阅读由one of his blog posts one of his blog posts提供.

原文链接：https://www.f2er.com/js/150260.html

javascript – 浏览器和节点之间有什么区别？

解决方法

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