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Jagadeesh AdaveniJagadeesh Adaveni 

When will i choose Controller and Extension controoler

Hi All,


When will i choose Controller and Extension controoler can you give me any explanation with example???

Best Answer chosen by Jagadeesh Adaveni
Michael VerhovskiMichael Verhovski
A custom controller is an Apex class that implements all of the logic for a page without leveraging a standard controller. Use custom controllers when you want your Visualforce page to run entirely in system mode, which does not enforce the permissions and field-level security of the current user.

A controller extension is an Apex class that extends the functionality of a standard or custom controller. Use controller extensions when:
  • You want to leverage the built-in functionality of a standard controller but override one or more actions, such as edit, view, save, or delete.
  • You want to add new actions.
  • You want to build a Visualforce page that respects user permissions. Although a controller extension class executes in system mode, if a controller extension extends a standard controller, the logic from the standard controller does not execute in system mode. Instead, it executes in user mode, in which permissions, field-level security, and sharing rules of the current user apply.
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