Program EntrySample;

var
  Field                 : String[10];
  LowEnd,HighEnd        : Real;
  Result,Value,
  Place,FieldSize,Times : Integer;
  Cursor,Ch             : Char;
  RangeOK               : Boolean;

procedure InputField;

label Bypass;

begin
    Field := '';
    Place := 0;
    Repeat
      Read(Kbd,Ch);
      If Length(Field)<=FieldSize then begin
        Case Ch of
          #8       : begin             {BackSpace key}
                       If Place=0 then begin  {avoid backspacing beyond}
                         Write(Trm,Chr(8));   {beginning of field      }
                         Write(' ');
                       end
                       else begin
                         Delete(Field,Place,1); {destructive backspace}
                         Place := Place-1;
                         Write(Trm,Chr(8));
                         Write(Cursor);
                         Write(Trm,Chr(8));
                       end;
                     end;
           #127    : begin;             {Delete Key}
                       If Place=0 then begin  {avoid backspacing beyond}
                         Write(Trm,Chr(8));   {beginning of field again}
                         Write(' ');
                       end
                       else begin
                         Delete(Field,Place,1); {destructive backspace}
                         Place := Place-1;
                         Write(Trm,Chr(8));
                         Write(Cursor);
                         Write(Trm,Chr(8));
                       end;
                     end;
           #13     : begin              {Carraige Return--End of input}
                       GoTo Bypass;     {for this field               }
                     end;
        else
          If Length(Field)<FieldSize then begin
            Place := Place+1;
            Write(Ch);
            Field := Field + Ch;
          end
          else begin
            If Ch <> Chr(13) then
              Write(Chr(7));            {Ring bell at terminal if at end of}
          end;                          {field and no RETURN key pressed   }
ByPass:
        end;
      end;
    Until Ch=Chr(13);
end;

procedure StripBlanks;            {don't use on Alpha-numeric fields...}
                                  {blanks there may be valid           }
begin
  Repeat
    Place := Pos(' ',Field);
    Delete(Field,Place,1);
    Place := Pos(' ',Field);
  Until Place=0;
end;


procedure RangeCheck;

begin
  Result := 0;                     {initialize error code}
  StripBlanks;                     {from FLDINPUT.PAS - pull out blanks}
  Val(Field,Value,Result);         {convert Field to a Number}
  If Result <> 0 then begin        {look for non-numeric characters} 
    Result := 0;                   {reset result code}
    RangeOK := False;
    Write(Chr(7));
    GoToXY(1,23); ClrEol;
    WriteLn('Input must be numeric.              ');
    Write('Press any key to continue...        ');
    Read(Kbd,Ch);
    GoToXY(1,23); ClrEol;
    GoToXY(1,24); ClrEol;
  end
  else begin
    If (Value < LowEnd) or (Value > HighEnd) then begin
      Write(Chr(7));
      RangeOK := False;
      GoToXY(1,23); ClrEol;
      WriteLn('Value not in allowable range.       ');
      Write('Press any key to continue...        ');
      Read(Kbd,Ch);
      GoToXY(1,23); ClrEol;
      GoToXY(1,24); ClrEol;
    end
    else begin
      RangeOK := True;
    end;             {checking range}
  end;               {checking result code}
end;                 {of RangeCheck}


begin                               {little sample program}
  ClrScr;
  Write('What do you use to delineate fields? (e.g., "_") :');
  Read(Cursor);
  ClrScr;
  GoToXY(30,4);
  Write('Entry Test');
  GoToXY(1,6);
  Write('Alpha Data: ');
  FieldSize := 8;
  GoToXY(20,6);
  For Place := 1 to FieldSize do begin
    Write(Cursor);
  end;
  GoToXY(20,6);
  InputField;
  GoToXY(20,6); ClrEol;
  WriteLn(Field);
  Field := '';
  Repeat
    GoToXY(1,8);
    Write('Enter a number between 1 and 1000 : ');
    FieldSize := 4;
    LowEnd := 1;
    HighEnd := 1000;
    GoToXY(40,8);
    For Place := 1 to FieldSize do begin
      Write(Cursor);
    end;
    GoToXY(40,8);
    InputField;
    StripBlanks;
    RangeCheck;
   Until RangeOK;
   Field := '';
   GoToXy(20,1);
   Write('Press any key to continue...');
   Read(Kbd,Ch);
   ClrScr;
end.