unit1.pas

本光盘是《Delphi 7应用教程》一书的配套光盘

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    GroupBox1: TGroupBox;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    ScrollBar1: TScrollBar;
    ScrollBar2: TScrollBar;
    ScrollBar3: TScrollBar;
    Label4: TLabel;
    procedure ScrollBar1Change(Sender: TObject);
    procedure ScrollBar2Change(Sender: TObject);
    procedure Edit1KeyPress(Sender: TObject; var Key: Char);
    procedure Edit1Exit(Sender: TObject);
    procedure Edit2Exit(Sender: TObject);
    procedure Edit3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation
var
  k1,k2:Integer;

{$R *.dfm}

procedure TForm1.ScrollBar1Change(Sender: TObject);
begin
  k1:=ScrollBar1.Position;
  Edit1.Text:=IntToStr(k1);//将滚动条的当前值赋给本金编辑框
end;

procedure TForm1.ScrollBar2Change(Sender: TObject);
begin
   k2:=ScrollBar2.Position;
   Edit2.Text:=IntToStr(k2);//将滚动条的当前值赋给利率编辑框
end;

procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);
begin
  if key=#13 then
    begin
      k1:=StrToInt(Edit1.Text);
      ScrollBar1.Position:=k1;//按Enter键时将编辑框的数值用滚动条显示出来
    end;
end;

procedure TForm1.Edit1Exit(Sender: TObject);
begin
  k1:=StrToInt(Edit1.Text);
  ScrollBar1.Position:=k1;//本金编辑框失去焦点时将把本金用滚动条显示出来
end;

procedure TForm1.Edit2Exit(Sender: TObject);
begin
  k2:=StrToInt(Edit2.Text);
  ScrollBar2.Position:=k2; //利率编辑框失去焦点时将把利率用滚动条显示出来
end;

procedure TForm1.Edit3Click(Sender: TObject);
var
  t:Real;
begin
  t:=k1*(1+k2/100);
  Edit3.Text:=FloatToStr(t);   //单击Edit3将显示本金与利息和，同时
  ScrollBar3.Position:=Trunc(t);  //通过滚动条显示出来
end;

end.