js override console.log if not defined

Which solution do you recommend, the second is simpler ( less code ), but there are drawbacks on using it ?

First: (Set a global debug flag)

// the first line of code
var debug = true;
try {
    console.log
} catch(e) {
    if(e) {
        debug=false;
    }
};
// Then later in the code
if(debug) {
    console.log(something);
}

Second: override console.log

try {
    console.log
} catch(e) {
    if (e) {
        console.log = function() {}
    }
};
// And all you need to do in the code is
console.log(something);

Neither, but a variation of the second. Lose the try...catch and check for existence of the console object properly:

if (typeof console == "undefined") {
    window.console = {
        log: function () {}
    };
}

console.log("whatever");

Or, in coffeescript:

window.console ?=
    log:-> #patch so console.log() never causes error even in IE.

Frankie

EDIT: Andy's answer is way more elegant than the quick hack I've posted below.

I generally use this approach...

// prevent console errors on browsers without firebug
if (!window.console) {
    window.console = {};
    window.console.log = function(){};
}

Suresh

I've faced a similar bug in my past, and I overcame it with the code below:

if(!window.console) {
    var console = {
        log : function(){},
        warn : function(){},
        error : function(){},
        time : function(){},
        timeEnd : function(){}
    }
}

I came across this post, which is similar to the other answers:

http://jennyandlih.com/resolved-logging-firebug-console-breaks-ie

The following will achieve what you are looking for:

window.console && console.log('foo');

window.console = window.console || {};
window.console.log = window.console.log || function() {};

来源：https://stackoverflow.com/questions/3767924/js-override-console-log-if-not-defined

标签

javascript

console

firebug