Example One

               This example demonstrates how to do some basic calculation for given data.

On this example just set following three events as shown here.

1)     Form create event

                          procedure TForm1.FormCreate(Sender: TObject);
                          begin
                              { Initialize the labels }
                              Label6.Caption:='0.00';
                              Label7.Caption:='0.00';
                              Label8.Caption:='0.00';
                             { Initialize the edit boxes }
                              Edit1.Text:='0.00';
                              Edit2.Text:='0.00';
                          end;

2)    (Calculate button) on click event 

                          procedure TForm1.Button1Click(Sender: TObject);
                          Var
                              V1, V2, VSum, VSub, VMul : Variant;
                          begin
                                { Variant type variables are very easy to use
                                these can hold any data type. And the advantage
                                is you can convert them into any data type easily }
                                V1:=Edit1.Text;
                                V2:=Edit2.Text;
                                { function Real() convert the variant to a real no. }
                                VSum:=Real(V1)+Real(V2);
                                VSub:=Real(V1)-Real(V2);
                                VMul:=Real(V1)*Real(V2);
                                { Put the results back in labels . . . }
                                Label6.Caption:=VSum;
                                Label7.Caption:=VSub;
                                Label8.Caption:=VMul;
                          end;

3)     (Exit button) on click event.

                          procedure TForm1.Button2Click(Sender: TObject);
                          begin
                               { Close the form }
                               Close;
                          end;

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