Contoh Latihan Delphi pilihan if, else if, dan else

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    Label7: TLabel;
    Label8: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Edit4: TEdit;
    Edit5: TEdit;
    Edit6: TEdit;
    Edit7: TEdit;
    Edit8: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure bersih;  //inisialisasi pembuatan prosedur bersih
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
procedure TForm1.bersih;  //awal pembuatan prosedur bersih
begin
  Edit1.Clear;
  Edit2.Clear;
  Edit3.Clear;
  Edit4.Clear;
  Edit5.Clear;
  Edit6.Clear;
  Edit7.Clear;
  Edit8.Clear;
end;   //akhir pembuatan prosedur bersih

procedure TForm1.Button1Click(Sender: TObject);
var nt,nq,nm,nu,na:Real;
begin
if Edit1.Text='' then begin
  Application.MessageBox('Inputkan Nilainya Terlebih dahulu' +#13+'Good Luck Coy!!'+#13+'Di Halaman http://delphianimelover.blogspot.com','Heng !',MB_ICONWARNING);
  Edit1.SetFocus;
  Exit;
end
else if Edit2.Text='' then Begin
  Application.MessageBox('Inputkan Nilainya Terlebih dahulu' +#13+'Good Luck Coy!!'+#13+'Di Halaman http://delphianimelover.blogspot.com','Heng !',MB_ICONWARNING);
  Edit2.SetFocus;
  Exit;
end
else if Edit3.Text=''  then Begin
  Application.MessageBox('Inputkan Nilainya Terlebih dahulu' +#13+'Good Luck Coy!!'+#13+'Di Halaman http://delphianimelover.blogspot.com','Heng !',MB_ICONWARNING);
  Edit3.SetFocus;
  Exit;
end
else if Edit4.Text='' then begin
  Application.MessageBox('Inputkan Nilainya Terlebih dahulu' +#13+'Good Luck Coy!!'+#13+'Di Halaman http://delphianimelover.blogspot.com','Heng !',MB_ICONWARNING);
  Edit4.SetFocus;
  Exit;
end;
  nt:=StrtoFloat(Edit1.Text);
  nq:=StrtoFloat(Edit2.Text);
  nm:=StrtoFloat(Edit3.Text);
  nu:=StrtoFloat(Edit4.Text);
  na:=(nt*0.1) + (nq*0.1) + (nm*0.4) + (nu*0.4);
  Edit5.Text:=FloatToStr(na);

  if (Edit5.Text<='100') and (Edit5.Text>='81') then begin
    Edit6.Text:='A';
    Edit7.Text:='4';
    Edit8.Text:='Excelent';
  end
  else if (Edit5.Text<='80') and (Edit5.Text>='66') then begin
    Edit6.Text:='B';
    Edit7.Text:='3';
    Edit8.Text:='Baik';
  end
  else if (Edit5.Text<='65') and (Edit5.Text>='56') then begin
    Edit6.Text:='C';
    Edit7.Text:='2';
    Edit8.Text:='Cukup';
  end
  else if (Edit5.Text<='55') and (Edit5.Text>='41') then begin
    Edit6.Text:='D';
    Edit7.Text:='1';
    Edit8.Text:='Kurang';
  end
  else if (Edit5.Text<='10') and (Edit5.Text>='0') then begin
    Edit6.Text:='E';
    Edit7.Text:='0';
    Edit8.Text:='Gagal';
  end;
end;
procedure TForm1.Button2Click(Sender: TObject);
begin
  Bersih;  //prosedur bersih dipanggil
end;

procedure TForm1.Button3Click(Sender: TObject);
begin
Self.Close;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  bersih;
  Label1.Caption:='Nilai Tugas';
  Label2.Caption:='Nilai Quiz';
  Label3.Caption:='Nilai MID';
  Label4.Caption:='Nilai UAS';
  Label5.Caption:='Nilai Angka';
  Label6.Caption:='Nilai Huruf';
  Label7.Caption:='Nilai Mutu';
  Label8.Caption:='Nilai Keterangan';
  Button1.Caption:='Hitung';
  Button2.Caption:='Clear';
  Button3.Caption:='Exit';
end;
end.