restemplate/UCRTHelper.pas

unit UCRTHelper;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, crt;

type
  TPromptMode = (pmNormal, pmPassword);

function Prompt(ACaption: String; AMode: TPromptMode = pmNormal): String; overload;
function Prompt(ACaption, ADefault: String; AMode: TPromptMode = pmNormal): String; overload;

implementation

function Prompt(ACaption: String; AMode: TPromptMode): String;
begin
  Result := Prompt(ACaption, '', AMode);
end;

function Prompt(ACaption, ADefault: String; AMode: TPromptMode): String;
var
  c: Char;
begin
  Write(ACaption);
  if ADefault <> '' then
    Write(' [', ADefault, ']');
  Write(': ');

  Result := '';
  repeat
    c := ReadKey;
    if (c = #8) and (Length(Result) > 0) then
    begin
      Write(#8, ' ', #8);
      SetLength(Result, Length(Result) - 1);
    end
    else if c > #31 then
    begin
      Result := Result + c;

      case AMode of
        pmNormal: Write(c);
        pmPassword: Write('*');
      end;
    end;
  until (c = #13) or (c = ^C);

  if (c = #13) and (Result = '') then
  begin
    Result := ADefault;
    Write(ADefault);
  end;

  if c = ^C then
    Result := ''; //Pretend that nothing happened.

  Writeln; //Always end the line
end;

end.