Удаление символов в строке

unit Unit1;
 
interface
 
uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, RegularExpressions;
 
type
  TForm1 = class(TForm)
    Button1: TButton;
    Memo1: TMemo;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private-Deklarationen }
  public
    { Public-Deklarationen }
  end;
 
var
  Form1: TForm1;
 
implementation
 
{$R *.dfm}
 
function RandomStr(ALen: Integer): String;
var i: Integer;
begin
  Result := '';
 
  for i := 0 to ALen do
    Result := Result + Chr(Random(26) + 65);
end;
 
function RandomSemicolon(ALen: Integer): String;
var i: Integer;
begin
  Result := '';
 
  for i := 1 to ALen do
    Result := Result + ';';
end;
 
procedure TForm1.Button1Click(Sender: TObject);
var i, j: Integer;
    S1, S2, S3: String;
 
    SL: TStringList;
 
    U: Cardinal;
begin
 
  U := GetTickCount;
 
  SL := TStringList.Create;
  for i := 1 to 1000000 do
    begin
 
      S1 := RandomSemicolon(Random(20));
      S3 := RandomSemicolon(Random(20));
 
      S2 := '';
      for j := 1 to Random(20) + 1 do
        begin
          S2 := S2 + RandomStr(Random(20)) + ';'
        end;
 
      SL.Add(S1 + S2 + S3)
    end;
 
  SL.SaveToFile('D:\112233.txt');
 
  FreeAndNil(SL);
 
  Memo1.Lines.Add('Create Time: ' + IntToStr(GetTickCount - U) + ' ms')
end;
 
procedure ParseData(AInList, AOutList: TStrings);
var M: TMatch;
    R: TRegEx;
begin
  R := TRegEx.Create('^[;]*(.*[\w\d]+)[;]*$', [roMultiLine]);
 
  M := R.Match(AInList.Text);
 
  repeat
 
    AOutList.Add(M.Groups[1].Value);
 
    M := M.NextMatch;
  until not M.Success;
 
end;
 
procedure TForm1.Button2Click(Sender: TObject);
var SL1: TStringList;
    SL2: TStringList;
    U: Cardinal;
begin
 
  U := GetTickCount;
 
  SL1 := TStringList.Create;
  SL2 := TStringList.Create;
 
  SL1.LoadFromFile('D:\112233.txt');
  Memo1.Lines.Add('Load Time: ' + IntToStr(GetTickCount - U) + ' ms');
 
  U := GetTickCount;
  ParseData(SL1, SL2);
  Memo1.Lines.Add('Parse Time: ' + IntToStr(GetTickCount - U) + ' ms');
 
  SL2.SaveToFile('D:\112233_result.txt');
 
  FreeAndNil(SL2);
  FreeAndNil(SL1);
 
end;
 
end.