Designing reusable code

Code modules in NAV are called codeunits. A codeunit does not have any user interface; the only purpose of a codeunit object is to store application code that can be called from other objects.

How to do it...

Now we will create a codeunit that will store functions common for objects in the current chapter, and move duplicated code from different objects into the codeunit.

1. Create a new codeunit in object designer. Save it as codeunit 50010 Item Certificate Mgt.

2. Declare a global function GetCertificateExpirationDate.

3. Select the function in C/AL Globals list and open its properties. By default, property Local is set to Yes. Change it to No to make the function accessible from other objects.

4. Open function parameters in C/AL Locals and declare one parameter:

   Name	Type	Length
   CertificateNo	Code	20

5. Still in C/AL Locals, add a local variable to the function:

   Name	DataType	Subtype
   ItemCertificateAction	Record	Item Certificate Action

6. Change the function...