如何在console.log（）中为每个值打印标签

Question

I'm having trouble figuring out how to customize console.log() so that it automatically prints out the label for each argument I pass into it. For example, I often do something like this, so that it's clear what each log is printing out:

console.log('firstName: ', firstName);

I would love to be able to simplify this to:

my.log(firstName);

Is there any way to pass the variable names of the caller args into console.log() ? Or is there another way to do this? My wish is that I don't have to type out the variable name twice, just the once. And ideally print out multiple arguments each with its own label on its own line in the console. I'm aware that I can access the arguments list, but I don't know how to un-eval() each argument to get just its variable name, if that makes sense. I'm hoping it's something super-easy I missed.

Answer 1

Doing it the way you want is impossible (the log function doesn't know what name you called things.) The way I work around this is to use the object shorthand {firstName} to create a temporary object.

You can then either use .log or .table to display it:

 const firstName = 'bob'; console.log({firstName}); console.table({firstName}); // It also works for multiple variables: const lastName = 'smith'; console.log({firstName, lastName}); 

Answer 2

You could use console.table() to print things in a more readable form:

(Look in the real console to see it.)

 var obj = { firstName: "name", lastName: "smith" }; function log(obj) { console.table(obj); } log(obj); 

Answer 3

Try this :

 var my = { log : function(name) { console.log('firstName: ', name); } }; my.log("Rohit");