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IndexChar function

In unit System

Search for a character in a memory range.

Declaration

pascal
function IndexChar(const buf; len: SizeInt; b: AnsiChar): SizeInt

Description

IndexChar searches the memory at buf for maximally len positions for the character b and returns it's position if it found one. If b is not found then -1 is returned. The position is zero-based. The IndexChar0 variant stops looking if a null character is found, and returns -1 in that case.

Errors

Buf and Len are not checked to see if they are valid values.

See also

Example: ex108

pascal
Program Example108;

{ Program to demonstrate the IndexChar function. }

Const
  ArraySize = 1000;
  MaxValue = 26;

Var
  Buffer : Array[1..ArraySize] of Char;
  I,J : longint;
  K : Char;

begin
  Randomize;
  For I:=1 To ArraySize do
    Buffer[I]:=chr(Ord('A')+Random(MaxValue));
  For I:=1 to 10 do
    begin
    K:=chr(Ord('A')+Random(MaxValue));
    J:=IndexChar(Buffer,ArraySize,K);
    if J=-1 then
      Writeln('Value ',K,' was not found in buffer.')
    else
      Writeln('Found ',K,' at position ',J,' in buffer');
    end;
end.

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