Javascript console.log（对象）与串联字符串 [英] Javascript console.log(object) vs. concatenating string

问题描述

我在node.js中运行它：

I'm running this in node.js:

> x = { 'foo' : 'bar' }
{ foo: 'bar' }
> console.log(x)
{ foo: 'bar' }
undefined
> console.log("hmm: " + x)
hmm: [object Object]
undefined

我不明白的是为什么 console.log（x）漂亮地打印对象，而字符串连接丑陋地打印它。更重要的是，打印的最佳方法是什么 hmm：{foo：'bar'} ？

What I don't understand is why console.log(x) "pretty-prints" the object, whereas string concatenation "ugly-prints" it. And more importantly, what's the best way to make it print hmm: { foo: 'bar' }?

推荐答案

+ x 将对象 x 强制转换为字符串，这只是 [object Object] ：

The + x coerces the object x into a string, which is just [object Object]:

http://jsfiddle.net/Ze32g/

漂亮的打印是一个非常好的，可能非常复杂的底层代码，有人实现作为控制台对象和日志方法的一部分。

The pretty printing is a very nice and probably very complex underlying code that someone implemented as part of the console object and the log method.

试试这个：

console.log("hmm: ", x);

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