When your source code contains the word "TImageList", hold down the Ctrl-Key and click on "TImagelist" -- this opens the unit in which TImageList is defined. TImageList has only published properties, therefore repeat the same procedure with the ancestors TDragImageList (in "TImageList = class(TDragImageList)") and TCustomImageList to get to the declaration of TCustomImageList in which all the methods and properties are listed. Scroll down a bit to see them.
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