判断某个文件夹是否存在是哪个函数?

Question

判断某个文件夹是否存在是哪个函数?
procedure TMainForm.BtnOpenFileClick(Sender: TObject);
begin
  IF eDIT3.Text = '' THEN
    Application.MessageBox('请输入具体的目录名称,再尝试!','系统提示',mb_ok+mb_iconinformation)
  else begin
    if DirExists(Edit3.Text) then{这里我出错!!!!}
    begin
        ShellExecute(handle,'open',PChar(Edit3.Text),nil,nil,SW_SHOWNORMAL);
    end
    else
    begin
      Application.MessageBox('您所指定的目录不存在,请核对后重新输入','系统提示',
      mb_ok+mb_iconinformation);
      edit3.SelectAll;
      Edit3.SetFocus;
    end;
  end;
end;
我用DirExists()函数不行啊!

Answer 1

用这个函数function DirectoryExists(const Directory: string): Boolean;

Answer 2

procedure TForm1.Button2Click(Sender: TObject);
begin
  if  DirectoryExists('c:\temp') then
  begin
    showmessage('exit');
  end
  else
  begin
     showmessage('not exit');
  end;
end;

Answer 3

function DirectoryExists(const Directory: string): Boolean;

Answer 4

function DirectoryExists(const Directory: string): Boolean;