Use the Introduce Local Extension dialog box to add logic when you cannot modify the original source code. The Introduce Local Extension dialog box appears after you have chosen the Refactor > Introduce Local Extension command while having a class method selected in the Source Editor.
The dialog box has the following fields:
The Equality field is disabled when Subtype is chosen in the Type field.
If you want the class to be moved immediately, click Refactor.
If you want to preview the change first, follow these steps:
The Refactoring window opens and displays a tree view of the code to be affected by the refactoring.