DelphiBasics freeandnil Procedure Free memory for an object and set it to nil SysUtils unit

procedure freeandnil(var ObjectReference);

Description The FreeAndNil procedure frees up the memory used by an object, and sets the object reference to nil.   It actually does this in reverse order - first dereferencing the object before deallocating the memory. This is a very clean way of freeing resources. Related commands FreeMem Free memory storage used by a variable GetMem Get a specified number of storage bytes Nil A pointer value that is defined as undetermined Null A variable that has no value  Download this web site as a Windows program.

Example code : Free and nil an object, and then try to do this again var   myList : TList; begin   // Create the list object   myList := TList.Create;   // And now free and nil this object   FreeAndNil(myList);   // We can safely do this twice - it ignores nil objects   FreeAndNil(myList); end; Show full unit code   No exception occurs - the second FreeAndNil does nothing.

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