The “this” keyword is an indispensable, yet often mis-understood, concept in JavaScript object-oriented programming. When used in a JavaScript constructor function, “this” refers to the specific instance of the Object. Through the “this” keyword, properties and methods can be assigned object, also known as a class.
For example:
function Square(intSideLength)
{
this.sideLength = intSideLength;
}
In the preceding example the “this” keyword is used to assign the variable “sideLength” as a property of the Square class.
The “this” keyword is also frequently passed as a parameter on JavaScript events, such as when a checkbox is clicked. In such an instance, “this” refers to the current object, the checkbox.
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