TOnIsDataEqual procedure type
Callback type to check whether 2 data types are equal.
Declaration
TOnIsDataEqual = function(ACache: TCache; AData1: Pointer;
AData2: Pointer): Boolean of objectArguments
ACache | TCache instance which calls the callback. |
AData1 | First data element pointer. |
AData2 | Second data element pointer. |
Function result
True if
AData1 and
AData2 are equal.Description
TOnIsDataEqual is a callback prototype; It is used by the
Add call to determine whether the item to be added is a new
item or not. The function returns
True if the 2 data pointers
AData1 and
AData2 should be considered equal, or
False when they are not.
For most purposes, comparing the pointers will be enough, but if the pointers are ansistrings, then the contents should be compared.
See also
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.