TCollection.FirstThat
Return first item which matches a test.
Declaration
Source position: objects.pp line 442
default
function FirstThat(Test: TCallbackFunBoolParam) : Pointer;
Description
This function returns the first item in the collection for which Test returns a non-nil result. Test is a function that accepts 1 argument: a pointer to an object, and that returns a pointer as a result.
Errors
None.
See also
Name | Description |
---|---|
TCollection.LastThat | Return last item which matches a test. |
Example
Program ex21;
{ Program to demonstrate the TCollection.FirstThat method }
Uses Objects,MyObject; { For TMyObject definition and registration }
Var C : PCollection;
M : PMyObject;
I : Longint;
Function CheckField (Dummy: Pointer;P : PMyObject) : Longint;
begin
If P^.GetField>56 then
Checkfield:=1
else
CheckField:=0;
end;
begin
C:=New(PCollection,Init(100,10));
For I:=1 to 100 do
begin
M:=New(PMyObject,Init);
M^.SetField(I);
C^.Insert(M);
end;
Writeln ('Inserted ',C^.Count,' objects');
Writeln ('first one for which Field>56 has index (should be 56) : ',
C^.IndexOf(C^.FirstThat(@CheckField)));
C^.FreeAll;
Dispose(C,Done);
end.