How do I override the default output of an object?

Question

Say in JavaScript I create a simple object:

function MyObj() {
    this.prop = \"property\";
}

Now if I create an instance of this and the

Answer 1

You could hook the browser console, and redefine it afterwards:

var obj = {
    name: "Joel",
    age: 32,
    toString: function() {
        return this.name + " is " + this.age + " years old.";
    }
};

var browserConsole = console;

console = {
    log: function(data) {
        if (typeof data === "object") {
            browserConsole.log(data.toString());
        } else {
            browserConsole.log(data);
        }
    }
}

console.log(obj);

Answer 2

MyObj.prototype.toString() = function() {} will work, but won't output to the console. If you do something like

console.log("The object says: " + obj);

... you will see the output of toString()

function MyObj() {
    this.prop = "property";
}
MyObj.prototype.toString = function() {
   return "My property 'prop' has the value: '" + this.prop + "'";
}
var obj = new MyObj();
console.log("the object says: " + obj);

// the object says: My property 'prop' has the value: 'property'

// Or call toString() explicitly
console.log(obj.toString());
// My property 'prop' has the value: 'property'