Node.js console.log（object）打印空对象

I'm curious about the way Node.js prints objects through console.log(object).

我很好奇Node.js通过console.log(对象)打印对象的方式。

I have the following code (from Learning Javascript Design Patterns book) under a file constructor.js

我在文件constructor.js下面有以下代码(来自Learning Javascript Design Patterns一书)

var defineProp = function(obj, key, value){
    var config = {
        value: value, 
        writable: true,
        configurable: true
    };
    Object.defineProperty(obj, key, config ); 
}

var person = Object.create(Object.prototype);


defineProp(person, "car", "Delorean"); 
defineProp(person, "dateOfBirth", "1981"); 
defineProp(person, "hasBeard", false); 

console.log(person); //This prints {} in Node.js

Running with that code with >node constructor.js prints an empty object. Chrome however, prints what I would expect if I run the code inside an HTML file.

使用> node constructor.js运行该代码将打印一个空对象。然而,如果我在HTML文件中运行代码,Chrome会打印出我所期望的内容。

console.log(person); //Chrome prints Object {car: "Delorean", dateOfBirth: "1981", hasBeard: false} 

Note: I can still print the attributes (such as console.log(person.car)) under Node, just not the object itself (such as console.log(person))

注意:我仍然可以在Node下打印属性(例如console.log(person.car)),而不是对象本身(例如console.log(person))

Why is this? Do Chrome and Node use separate prototypes for the console object, even though they share the same javascript engine?

为什么是这样? Chrome和Node是否为控制台对象使用单独的原型,即使它们共享相同的JavaScript引擎?

1 个解决方案

#1

console.log() in node utilizes util.inspect(), which uses Object.keys() on objects, which returns only own enumerable properties. Also, by default, Object.defineProperty() sets enumerable: false if you do not explicitly set it to true.

node.log()在节点中使用util.inspect(),它在对象上使用Object.keys(),它只返回自己的可枚举属性。此外,默认情况下,Object.defineProperty()设置可枚举:如果未将其显式设置为true,则设置为false。