Bind event handler to "console.log" JavaScript event

Question

My script sends text to the console output from several places in Javascript (see examples), how do I bind an event handler function to the log function itself so that a function is executed each time the event is triggered?

try {
    //some code
} catch(e) {
    console.log("error: "+e)
}

function x(n) {
    //some code
    console.log(str)
}

Write an event binding and have console.log("Some message"); in the function? — Justin Wood
– Justin Wood, Commented Dec 21, 2013 at 21:15
Redefine the log function to trigger an event you can bind a handler to. — towr
– towr, Commented Dec 21, 2013 at 21:18

Community · Accepted Answer · 2017-05-23 10:31:28Z

11

I would override console.log (but store it in a different variable, in case we want to use it) like so:

var nativeLog = console.log.bind(console) //store native function

console.log = function(text){ //override
    nativeLog("<<<" + text)
}

Abbreviating console.log in JavaScript

edited May 23, 2017 at 10:31

CommunityBot

11 silver badge

answered Dec 21, 2013 at 21:19

TastySpaceApple

3,2051 gold badge22 silver badges27 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

towr Over a year ago

You can create a new event that gets trigger from the overridden console.log, e.g. jsfiddle.net/SzE34

adeneo Over a year ago

@towr - that would be an illegal invocation of the function you're currently overwriting.

towr Over a year ago

@adeneo I don't quite understand what you mean, though I figure it has to do with the (probably better) way TastySpaceApple stores the native function? My intent was more to add an event to the mix, though. --- Firefox didn't complain, but if you can give me some pointers to better my javascript I'd appreciate it.

adeneo Over a year ago

@towr - chrome does throw an "illegal invocation" error, and using bind() would be better, otherwise the example of creating an event and triggering it is spot on, and surely the way to do it.

Collectives™ on Stack Overflow

Bind event handler to "console.log" JavaScript event

1 Answer 1

4 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related