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TStrCollection.Compare function

Member of TStrCollectionIn unit Objects

Compare two strings in the collection.

Declaration

pascal
function Compare(Key1: Pointer; Key2: Pointer): Sw_Integer; virtual

Description

TStrCollection overrides the Compare function so it compares the two keys as if they were pointers to strings. The compare is done case sensitive. It returns

-1
if the first string is alphabetically earlier than the second string.
0
if the two strings are equal.
1
if the first string is alphabetically later than the second string.

Errors

None.

See also

Example: ex38

pascal
Program ex38;

{ Program to demonstrate the TStrCollection.Compare method }

Uses Objects,Strings;

Var C : PStrCollection;
    S : String;
    I : longint;
    P : Pchar;

begin
  Randomize;
  C:=New(PStrCollection,Init(120,10));
  C^.Duplicates:=True; { Duplicates allowed }
  Writeln ('Inserting 100 records at random places.');
  For I:=1 to 100 do
    begin
    Str(Random(100),S);
    S:='String with value '+S;
    P:=StrAlloc(Length(S)+1);
    C^.Insert(StrPCopy(P,S));
    end;
  For I:=0 to 98 do
    With C^ do
      If Compare (At(I),At(I+1))=0 then
        Writeln ('Duplicate string found at position ',I);
  Dispose(C,Done);
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.