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Franco Torres
Asked: 2022-01-23 07:14:23 +0800 CST 2022-01-23 07:14:23 +0800 CST

How to remove [ ] from a string in Pascal

  • 772

I'm reneging on a function to remove [] from a string. I need to remove the brackets from a string, but the problem I'm having is that those [] can be anywhere in the string.

The code I am using is the following:

function quitarCorchetes(descripcion: string): String;
Begin
  if descripcion <> '' then
    if descripcion[1] = '[' then
      descripcion := Copy(descripcion,2,Length(descripcion)-2);
  Result := descripcion;
End;

This code works for strings that are "[algo adentro]", the problem is when the string is of type "[algo] mas descripcion"or "descripcion [algo]".I don't know if there is any way to do it using a regular expression or something like that. I am very new to pascal and don't have much idea.

pascal

2 Answers

  1. Best Answer
    function quitarCorchetes(descripcion: string): String;
begin
  for i:=1 to length(descripcion) do
  begin
     if(descripcion[i] = '[') or (descripcion[i] = ']')
     begin
        delete(descripcion, i, 1);
     end;
  end;

  Result:=descripcion;
end;

    You go through the string through a cycle and for each position of the string you ask if the character '[' or the character ']' is found, if any of those characters are found, they are deleted from the string through the Delete procedure.

    Delete deletes a substring within a string and takes 3 parameters, the first parameter is the string, the second is the starting position, and the third parameter is the number of characters to delete.

    Ex:

    cadena = 'abcdefghi';
delete(cadena, 2, 2);

    Here from the string starting at position 2, 2 characters are going to be deleted, therefore the result would be abefghi, that is, the characters c and d were deleted from the original string

    • 2

  2. You can use the function Pos()to determine the position of a character within a string and, if found within it, remove it, for example this function will remove all occurrences of a character within a string:

    function RemoverTodoCaracter(s: string; Caracter: Char): string;
var
  PosCar: Integer;
begin
  Result := s;
  repeat
    PosCar := Pos(Caracter, Result);
    if PosCar <> 0 then
      Delete(Result, PosCar, 1);
  until PosCar = 0;
end;

    You could, based on this, write another routine to remove the brackets:

    function RemoverCorchetes(s: string): string;
begin
  Result := RemoverTodoCaracter(s, '[');
  Result := RemoverTodoCaracter(Result, ']');
end;

    Finally, if you work with a modern version of Pascal (Delphi, FreePascal), you can use the function StringReplace, which is found in the unit SysUtils:

    function RemoverCorchetes(s: string): string;
begin
  Result := StringReplace(s, '[', '', [rfReplaceAll]);
  Result := StringReplace(Result, ']', '', [rfReplaceAll]);
end;
    • 1