• Introduction COC (chain of command) & Method Wrapping In Microsoft Dynamics 365 finance and operations –
• Microsoft D365 Finance and operations supports very powerful feature called COC or method wrapping.
• In past, Microsoft Dynamics AX/Axapta supports overlayering where you can overlayer Microsoft classes, table methods etc directly by placing your code in the middle, bottom or top if standard code. Below is screenshot and example for your reference. In below screenshot i placed my custom code in the middle of standard method by using overlayering.

• In Microsoft Dynamics 365 finance and operations (After version 8.0) , you cannot overlayer code as everything is sealed now. We have to use COC or method wrapping.Microsoft has improved the Functionality of Class extension for D365 FO by adding wrap logic around methods which are defined in the base class that you are augmenting. You can Wrap or do Chain of command (COC) of public and protected methods.
• In below screenshot i am using method wrapping or class extension of standard class which is different from Microsoft Dynamics AX overlayering approach.

• Next keyword means to call the orginal method “ChecItemPostingDate” of standard class “InventUpdate”
• You can get values of Global Variables of in your extension class of your parent class or main class.
• Final Modifier means The method can’t be overridden in any class that derives from its class.
• Here are one more example where we are using COC (chain of commands) in Table methods.

Benefits Of Using Change Of Commands instead of Old Overlayering approach in Microsoft Dynamics 365 finance and operations

1. Easy Future upgrades and version enhancements as you are not doing overlayering in standard classes or methods or objects & keeping you separate extension classes.
2. Neat & Clean development as no need to compile whole code librarary.