javascript basics - VI

javascript basics - reflection, extension methods via prototype

by deshpandeakhil

JavaScript

var f = function(arg) {
    if (arg != null) {
        document.write(arg);
        document.write("<br/>");
    } else if (arg == undefined) {
        document.write("undefined<br/>");
    }
    else {
        document.write("<br/>");
    }
};

var person = {
    name: "Michael Jordan",
    age: 49,
    doWork: function(arg){f(arg);},
    nicknames: ["Air Jordan", "His Airness", "MJ"]
};

//iterate and reflect properties
for(var prop in person){
    f("key: " + prop + ", value: " + person[prop]);
};
    
//extension methods can be created by adding to prototype
// Here we are adding and extension method to Object to determine if an object is an array
Object.prototype.isArray = function(){
    return this instanceof Array;
};
f(person.isArray());f(person.nicknames.isArray());