zcaceres

The Revealing Module Pattern in Javascript

Zach Caceres

Javascript does not have the typical 'private' and 'public' specifiers of more traditional object oriented languages like C# or Java. However, you can achieve the same effect through the clever application of Javascript's function-level scoping. The Revealing Module pattern is a design pattern for Javascript applications that elegantly solves this problem.

The central principle of the Revealing Module pattern is that all functionality and variables should be hidden unless deliberately exposed.

Let's imagine we have a music application where a musicPlayer.js file handles much of our user's experience. We need to access some methods, but shouldn't be able to mess with other methods or variables.

Using Function Scope to Create Public and Private Methods

akkidas

-- If you want to generate a new Guid (uniqueidentifier) in SQL server the you can simply use the NEWID() function.

SELECT NEWID()
GO
-- This will return a new random uniqueidentifier e.g.
E75B92A3-3299-4407-A913-C5CA196B3CAB
To select this Guid in in a variable

--assign uniqueidentifier in a variable
DECLARE @EmployeeID uniqueidentifier