JS Create function: JS Create object object How to inherit and some tool functions

function Rectangle (W, h) {
This.width = W;
This.height = h;
}
Rectangle.prototype.area = function () {return this.width * this.height;}; The instance method of a class suggests defining a method for a prototype object rather than a constructor definition method
Rectangle.prototype.toString = function () {return "[+ This.width +", "+ This.height +]";};/ /This performance is better, all objects share the same method, object inherits the object prototype
function Positionrectangle (x, Y, W, h) {
Rectangle.apply (This, [w, H]); Calling the constructor of the parent class
This.superclass (W, h); Call the constructor of the parent class by appending the property to the stereotype
this.x = x;
This.y = y;
}
Positionrectangle.prototype = The prototype of the new Rectangle ()///subclass is an instance of the superclass
PositionRectangle.prototype.superclass = rectangle;//Add attributes to the prototype to facilitate the invocation of the parent class constructor
PositionRectangle.prototype.constructor = Positionrectangle; Set the constructor of the prototype
Delete positionrectangle.prototype.width;//deletes the properties created by the superclass constructor in the prototype
Delete PositionRectangle.prototype.height; Remove a property created by a superclass constructor in a prototype
PositionRectangle.prototype.contains = function (x, y) {
Return (This.x < x && x < this.x + This.width, this.y < y && y < this.y + this.height);
}
PositionRectangle.prototype.toString = function () {
Return ' ("+ this.x +", "+ This.y +") "+ this.superclass.prototype.toString.apply (this); Call method with the same name as the parent class
};
function Getpropertyname (/*object */o,/*option array*/r) {
var r = r [];
for (var name in O) {
R.push (name);
}
return R;
}
function copyproperties (/*object from*/from,/*object to*/to) {
var to = to {};
For (Var p. from) {
TO[P] = from[p];
}
return to;
}
function copyundefinedproperties (/*object from*/from,/*object to*/to) {
For (Var p. from) {
if (to[p] = = undefined)
TO[P] = from[p];
}
return to;
}
function Filterarray (/*array*/a,/*predicate*/predicate) {This article links http://www.cxybl.com/html/wyzz/JavaScript_Ajax/ 20121116/33888.html