Object Javascript
var myCat = {
"name": "hachii",
"legs": 4,
"color": "white",
};
myCat.speck = "meo";
delete myCat.color;
Lookup with Object
val ="alpha";
var arrData = {
"alpha":"Adams",
"bravo": "Boston",
"charlie": "Chicago",
"delta": "Denver",
"echo":"Easy",
"foxtrot": "Frank"
};
result = arrData[val];
Testing Object for Properties
- .hasOwnProperty(propname)
var arrData = {
"alpha":"Adams",
"bravo": "Boston",
"charlie": "Chicago",
"delta": "Denver",
"echo":"Easy",
"foxtrot": "Frank"
};
a = "alpha";
b= "beta";
arrData.hasOwnProperty(a); // true
arrData.hasOwnProperty(b); // false
var Car = function() {
this.wheels = 4;
this.engines = 1;
this.seats = 5;
};
engines : 1,
seats : 5
};
We can use this:
myCar.wheels = 4;
myCar.name = "Ferrari"; // we can create its attribute
var myCar = new(4,8,2);
Example of construction Function
var Car = function() {
this.wheels = 4;
this.engines = 1;
this.seats = 5;
};
Create Instance of Object with construction Function
var myCar = new Car();
// now
myCar = {
wheels : 4,engines : 1,
seats : 5
};
We can use this:
myCar.wheels = 4;
myCar.name = "Ferrari"; // we can create its attribute
Parameter to Constructor Function
var Car = function(wheel,engin, seat) {
this.wheels = wheel;
this.engines = engin;
this.seats = seat;
};
var myCar = new(4,8,2);
// now
myCar = {
wheels : 4,
engines : 8,
seats : 2
};
Object Properties Private vs Public
var Bike = function() {
// gear is private and only assisible inside
var gear;
// these are public methods
this.setGear = function(change) {
gear = change;
};
this.getGear = function() {
return gear;
};
};