A point of confusion sometimes is that to log a text message along with the contents of one of your objects using console.log, you have to pass each one of the two as a different argument. This means that you have to separate them by commas because if you were to use the + operator to concatenate the outputs, this would implicitly call the .toString() method of your object. This in most cases is not explicitly overriden and the default implementation inherited by Object doesn't provide any useful information.

在控制台尝试的例子:

>>> var myObj = {foo: 'bar'}
undefined
>>> console.log('myObj is: ', myObj);
myObj is: Object { foo= "bar"}

然而，如果你试图连接信息文本消息与对象的内容，你会得到:

>>> console.log('myObj is: ' + myObj);
myObj is: [object Object]

请记住，console。log实际上可以接受任意多的参数。

举个例子——假设你想知道哪行代码可以运行你的程序(在它崩溃之前!)，只需输入

console.log("You made it to line 26. But then something went very, very wrong.")

这与jQuery无关。console.log()引用控制台对象的日志函数，该函数提供了将信息记录到浏览器控制台的方法。这些方法仅用于调试目的，不应依赖于将信息呈现给最终用户。

除了上面提到的用法，console.log也可以在node.js中打印到终端。使用express(例如)创建的服务器可以使用console.log写入输出记录器文件。

console.log与jQuery无关。

它将消息记录到调试控制台，例如Firebug。

您可以使用它在Firefox的Firebug或WebKit浏览器的JavaScript控制台中调试JavaScript代码。

var variable;

console.log(variable);

它将显示变量的内容，即使它是一个数组或对象。

它类似于print_r($var);PHP。