JavaScript Functions

JavaScript functions allow us to define a block of code and we can call it as many times as we want.

A JavaScript function can be declared by using the function keyword, followed by a unique function name, a list of parameters and a statement block surrounded by curly braces.


    function functionName (parameter1, parameter2, ...)
        //code to be executed

Example 1:

    function hello()
        alert (“Hello everyone!”);

We can call above function as hello().

Example 2:

    function getSquare (num)
        return ( num * num );

We can call above function as getSquare(5) and it will return the square of 5 i.e.25.

Anonymous functions

An anonymous function is an unnamed function does not have any name.

It must be assigned to a variable.


    var msg = function()
        alert(“Hello Everyone!”);

The above anonymous function can be invoked as msg().