| 25. 9. 1. Inheritance |
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Call the constructor from base class |
A constructor assigns all properties and methods using the this keyword. |
You can make the constructor of BaseClass into a method of SubClass and call it. |
After the calling, subClass receives the properties and methods defined in BaseClass's constructor. |
In the following code, the 'newMethod' is assigned to BaseClass. |
Then, the 'newMethod' is called, passing the color argument from the SubClass constructor. |
The final line of code deletes the reference to BaseClass so that it cannot be called later on. |
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function BaseClass(sColor) {
this.color = sColor;
this.sayColor = function () {
alert(this.color);
};
}
function SubClass(sColor) {
this.newMethod = BaseClass;
this.newMethod(sColor);
delete this.newMethod;
}
var objA = new BaseClass("red");
var objB = new SubClass("blue");
objA.sayColor();
objB.sayColor();
objB.sayName();
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