Try and Catch In Pascal

Question

I\'m using Dev-Pas 1.9.2 and am trying to make sure the program doesn\'t crash when a symbol or a letter value is entered.

I\'ve googled and googled and can\'t find

Answer 1

Change your code to accept a Char instead; if you need an integer for some reason, handle the conversion afterward.

This works in Delphi; unless you can't use sets like ['1'..'4','9'] and set operators, it should work fine.

Function GetMenuChoice : Char;
Var
  OptionChosen : Char;
Begin
  repeat
    Write('Please enter your choice: ');
    Readln(OptionChosen);

    If not (OptionChosen in ['1'..'4', '9'])
      Then
        Begin
          Writeln;
          Writeln('That was not one of the allowed options.  Please try again: ');
        End;
  until OptionChosen in ['1'..'4', '9'];
  GetMenuChoice := OptionChosen;
End;

If you absolutely need a number to be returned, change the return type back to integer (or byte) and then change the final line to:

GetMenuChoice := Ord(OptionChosen) - 48;  

or

GetMenuChoice := Ord(OptionChosen) - Ord('0');