Object.getOwnPropertyNames = Object.getOwnPropertyNames || function (object) {
    var props = [];
    for (var i in object) {
        if (object.hasOwnProperty(i)) {
            props.push(i);
        }
    }
    return props;
};

Object.keys = Object.keys || function (object) {
    var keys = [];
    for (var i in object) {
        keys.push(i);
    }
    return keys;
};

Object.getPropsAndValues = function (object) {
    var result = '';
    for (var i in obj) {
        if (object.hasOwnProperty(i)) {
            result += i + ': ' + '\n';
        }
    }
    // strip unneccessary newline at end
    result = result.replace(/\n$/);
};

// Console

>>> var obj = {a: 1, b: 2};
>>> Object.prototype.c = 3;
>>>
>>> Object.getOwnPropertyNames(obj);
["a", "b"]
>>> Object.keys(obj);
["a", "b", "c"]
>>> Object.getPropsAndValues(obj);
"a: 1
b: 2"