如何扩展console.log？

Question

Is there anyway to write a prototype function, or a function that runs whenever console.log is called? (And grabs the console.log parameter). I am about 100 KB's in for my web-based game server, and have hundreds of console.logs throughout my code. I would love to use the console log data and use the information later in a web-based admin panel or whatnot.

Oh, and I'm Using nodejs and FS . Writing to a file is no problem, I know how to do that, but just catching the console.log is the issue. Any idea?

Answer 1

Just replace console.log with your own function, like this

// Store the original version, so that you can fall back to it
var originalLogger = console.log,
    fs = require("fs"),
    writeStream = fs.createWriteStream("logs.txt");

console.log = function () {

    // Do your custom logging logic
    for (var i = 0; i < arguments.length; i++) {
        writeStream.write(arguments[i]);
    }

    // You can still call the original `console.log`, with all the `arguments`
    originalLogger.apply(this, arguments);
}

console.log("Welcome");

Answer 2

You can reset console.log to your custom log function, demo code:

var fs = require('fs');
var util = require('util');

var l = fs.createWriteStream('abc');
console.log = function () {
    var args = Array.prototype.slice.call(arguments)
    l.write(util.format.apply(util, args));
    l.write('\n');
}