在此页

• 句法
• log() 和 dir() 的区别
• 日志对象
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

控制台 方法 log() outputs a message to the web console. The message may be a single string (with optional substitution values), or it may be any one or more JavaScript objects.

注意： 此特征可用于 Web 工作者 .

句法

console.log(obj1 [, obj2, ..., objN]);
console.log(msg [, subst1, ..., substN]);
					

参数

obj1 ... objN

A list of JavaScript objects to output. The string representations of each of these objects are appended together in the order listed and output. Please be warned that if you log objects in the latest versions of Chrome and Firefox what you get logged on the console is a reference to the object , which is not necessarily the 'value' of the object at the moment in time you call console.log() , but it is the value of the object at the moment you open the console.

msg

A JavaScript string containing zero or more substitution strings.

subst1 ... substN

JavaScript objects with which to replace substitution strings within msg . This gives you additional control over the format of the output.

见 把文本输出到控制台 在文档编制的 console 了解细节。

log() 和 dir() 的区别

You might ask yourself what's the difference between console.dir() and console.log() .

Another useful difference in Chrome exists when sending DOM elements to the console.

预告：

• console.log 以像 HTML 树打印元素
• console.dir 以像 JSON 树打印元素

具体来说， console.log gives special treatment to DOM elements, whereas console.dir does not. This is often useful when trying to see the full representation of the DOM JS object.

有更多信息在 Chrome 控制台 API 参考 关于此和其它函数。

日志对象

不使用 console.log(obj) ，使用 console.log(JSON.parse(JSON.stringify(obj))) .

This way you are sure you are seeing the value of obj at the moment you log it. Otherwise, many browsers provide a live view that constantly updates as values change. This may not be what you want.

规范

规范	状态	注释
控制台 API 在该规范中的 console.log() 定义。	实时标准	初始定义

浏览器兼容性

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	桌面						移动
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
log	Chrome 1	Edge 12	Firefox 4	IE 8	Opera 10.5	Safari 3	WebView Android 1	Chrome Android 18	Firefox Android 4	Opera Android 11	Safari iOS 1	Samsung Internet Android 1.0
Substitution strings	Chrome Yes Yes In version 28, if a negative value is passed to %d, it will be rounded down to the closest negative integer, so -0.1 becomes -1.	Edge 12 12 Before Edge 79, %c 不支持。 Before Edge 79, %d outputs a 0 if the specified value isn't a number.	Firefox 9	IE 10 10 %c 不支持。 %d outputs a 0 if the specified value isn't a number.	Opera ?	Safari ?	WebView Android Yes Yes In version 28, if a negative value is passed to %d, it will be rounded down to the closest negative integer, so -0.1 becomes -1.	Chrome Android Yes Yes In version 28, if a negative value is passed to %d, it will be rounded down to the closest negative integer, so -0.1 becomes -1.	Firefox Android 9	Opera Android ?	Safari iOS ?	Samsung Internet Android Yes Yes In Samsung Internet 1.5, if a negative value is passed to %d, it will be rounded down to the closest negative integer, so -0.1 becomes -1.

图例

完整支持

完整支持

兼容性未知 ?

兼容性未知

见实现注意事项。

另请参阅

• Opera Dragonfly 文档编制：控制台
• MSDN：使用 F12 工具控制台查看错误和状态
• Firebug wiki: Console API - Firebug supports additional features in its console.log() implementation, such as styled logging .
• NodeJS: 控制台 API

元数据

• 最后修改： Jul 30, 2020

相关话题

1. 控制台 API
2. 控制台
3. 方法

   1. assert()
   2. clear()
   3. count()
   4. countReset()
   5. debug()
   6. dir()
   7. dirxml()
   8. error()
   9. group()
   10. groupCollapsed()
   11. groupEnd()
   12. info()
   13. log()
   14. profile()
   15. profileEnd()
   16. table()
   17. time()
   18. timeEnd()
   19. timeLog()
   20. timeStamp()
   21. trace()
   22. warn()
4. 控制台 API 相关页面

   1. Window.console
   2. WorkerGlobalScope.console