[angvelem]

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Returns the index value of the first character in a specified substring that occurs in a given string.

Delphi syntax:

function Pos(Substr: string; S: string): Integer;

Description

In Delphi, Pos searches for a substring, Substr, in a string, S. Substr and S are string-type expressions.

Pos searches for Substr within S and returns an integer value that is the index of the first character of Substr within S. Pos is case-sensitive. If Substr is not found, Pos returns zero.

Код:

var
  S : string;
begin
  S := '   123.5';
  { Convert spaces to zeros }
  while Pos(' ', S) > 0 do
    S[Pos(' ', S)] := '0';
end;