PC Plus SuperCD (UK) 1997 May/PC Plus Super CD Issue 127 (May 1997).iso/handson/handson.exe/FRUNIT4.PAS

Pascal/Delphi Source File | 1997-01-31 | 5.5 KB | 191 lines

unit Frunit4;
{ PC Plus sample Delphi program. A simple French verb conjugator - mark 4 }
{ This now deals with regular ER, IR and RE verbs. It illustrates the use }
{ of standard Pascal procedures                                           }
{                                                                         }
{ Note the use of WITH                                                    }
{      in     With Form1.ListBox1.Items do                                }
{                                                                         }
{ Also the 'shortcut' way of calling the JePlusStem function              }
{ i.e Instead of declaring an intermediate string variable, 's'           }
{ and then using the expressions:                                         }
{             s := JePlusStem(vStem);                                     }
{             Add( s + 'e');                                              }
{ this has all been done in one go:                                       }
{             Add(JePlusStem(vStem) + 'e');                               }



interface

uses
  SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
  Forms, Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    ListBox1: TListBox;
    Edit1: TEdit;
    Label1: TLabel;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}
procedure ConjugateALLER;
begin
  With Form1.ListBox1.Items do
  begin
   Clear;
   Add('Je vais');
   Add('Tu vas');
   Add('Il va');
   Add('Elle va');
   Add('Nous allons');
   Add('Vous allez');
   Add('Ils vont');
   Add('Elles vont');
  end;
end;

procedure ConjugateAVOIR;
begin
  With Form1.ListBox1.Items do
  begin
   Clear;
   Add('J''ai');
   Add('Tu as');
   Add('Il a');
   Add('Elle a');
   Add('Nous avons');
   Add('Vous avez');
   Add('Ils ont');
   Add('Elles ont');
  end;
end;

procedure ConjugateETRE;
begin
  With Form1.ListBox1.Items do
  begin
   Clear;
   Add('Je suis');
   Add('Tu es');
   Add('Il est');
   Add('Elle est');
   Add('Nous sommes');
   Add('Vous etes');
   Add('Ils sont');
   Add('Elles sont');
  end;
end;

function JePlusStem( vStem : string ) : string;
{ Function checks to see if a vowel begins the verb. If so           }
{ it retuns "J'" plus verb stem. Else, it reurns "Je " plus verbStem }
Const { declare vowels as a set of characters                        }
  vowels : set of char = ['a','e','i','o','u','y'];
begin { see if 1st letter of vStem is in the set named 'vowels'      }
   if vStem[1] in vowels then
      JePlusStem := 'J''' + vStem
   else
      JePlusStem := 'Je ' + vStem;
end;


procedure ConjugateERverb( vStem : string );
begin
   with Form1.ListBox1.Items do
   begin
     Clear;
      { call the JePlusStem function to return the Je form }
     Add(JePlusStem(vStem) + 'e');
     Add('Tu ' + vStem + 'es' );
     Add('Il ' + vStem + 'e' );
     Add('Elle ' + vStem + 'e' );
     Add('Nous ' + vStem + 'ons' );
     Add('Vous ' + vStem + 'ez' );
     Add('Ils ' + vStem + 'ent');
     Add('Elles ' + vStem + 'ent');
   end;
end;

procedure ConjugateREverb( vStem : string );
begin
   with Form1.ListBox1.Items do
   begin
     Clear;
     Add(JePlusStem(vStem) + 's');
     Add('Tu ' + vStem + 's' );
     Add('Il ' + vStem  );
     Add('Elle ' + vStem  );
     Add('Nous ' + vStem + 'ons' );
     Add('Vous ' + vStem + 'ez' );
     Add('Ils ' + vStem + 'ent');
     Add('Elles ' + vStem + 'ent');
   end;
end;

procedure ConjugateIRverb( vStem : string );
begin
   with Form1.ListBox1.Items do
   begin
     Clear;
     Add(JePlusStem(vStem) + 'is');
     Add('Tu ' + vStem + 'is' );
     Add('Il ' + vStem + 'it' );
     Add('Elle ' + vStem + 'it' );
     Add('Nous ' + vStem + 'issons' );
     Add('Vous ' + vStem + 'issez' );
     Add('Ils ' + vStem + 'issent');
     Add('Elles ' + vStem + 'issent');
   end;
end;

procedure TForm1.Button1Click(Sender: TObject);
var                  { --- Declare 3 string variables --- }
  verb,              { the verb specified by the user     }
  verbStem,          { the verb minus its 2-letter ending }
  verbEnd : string;  { the 2-letter ending                }
begin
  verb := LowerCase( Edit1.Text );{ make text lower case  }
       { check that the user has entered something...     }
  if verb = '' then
     Caption := 'You must enter a verb!'
  else
  begin {... if so, then                              }
        { find the stem and the ending of the verb    }
    verbStem := copy( verb, 1, length(verb)-2 );
    verbEnd  := copy( verb, length(verb) -1, 2 );
    Caption  := 'This is an ' + verbEnd + ' verb.';
        { find type of verb and call appropriate proc }
        { ---- check for IRREGULAR verbs ------------ }
    if verb = 'aller' then
       conjugateALLER
    else if verb = 'etre' then
       conjugateETRE
    else if verb = 'avoir' then
       conjugateAVOIR
       { ------ then deal with REGULAR verbs -------- }
    else if verbEnd = 'er' then
       ConjugateERverb( verbStem )
    else if verbEnd = 're' then
       ConjugateREverb( verbStem )
    else if verbEnd = 'ir' then
       ConjugateIRverb( verbStem )
    else         { if this isn't an ER, RE or IR verb, show error msg... }
       Caption := 'You must enter an ER, RE or IR verb!';
  end;
end;

end.