listform.pas

列表框_组合框_滚动条 列表框_组合框_滚动条 列表框_组合框_滚动条

unit ListForm;

interface

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

type
  TMainForm = class(TForm)
    ListBox1: TListBox;
    ComboBox1: TComboBox;
    ScrollBar1: TScrollBar;
    procedure FormCreate(Sender: TObject);
    procedure ComboBox1Select(Sender: TObject);
    procedure ScrollBar1Scroll(Sender: TObject; ScrollCode: TScrollCode;
      var ScrollPos: Integer);
    procedure ListBox1KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

{$R *.dfm}

procedure TMainForm.FormCreate(Sender: TObject);
begin
   MainForm.caption:='列表框&组合框※滚动条';
   combobox1.Clear;           //清除原有的项
   combobox1.Items.Add('北京');//加入初始的各项
   combobox1.Items.Add('上海');
   combobox1.Items.Add('纽约');
   combobox1.Items.Add('伦敦');
   combobox1.Items.Add('东京');
   combobox1.Items.Add('巴黎');
   combobox1.Items.Add('萨达姆');
   combobox1.Items.Add('小不死：）');
   scrollbar1.Max:=7;     //设置滚动范围
   scrollbar1.PageSize:=1;
   scrollbar1.Min:=0;
   listbox1.Sorted:=True;   //设置listbox的排序特性
   listbox1.MultiSelect:=True; //设置可以选择多行
   listbox1.ExtendedSelect:=True;
end;

procedure TMainForm.ComboBox1Select(Sender: TObject);
begin
  listbox1.Items.Add(combobox1.Text);//将组合框的项加入列表框
end;

procedure TMainForm.ScrollBar1Scroll(Sender: TObject; ScrollCode: TScrollCode;
  var ScrollPos: Integer);
 var
  i:integer;
begin
  combobox1.Text:='';
  i:=scrollbar1.Position;
  combobox1.SelText:=combobox1.Items.Strings[i];
end;

procedure TMainForm.ListBox1KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
  var
   i:integer;
   j:integer;
begin
      if(Key=VK_DELETE) then //如果按下了del键盘
      begin
          i:=listbox1.Items.Count;
          if(i>0) then  // 如果至少有一项
          begin         //从最后向前删除，这是因为如果从前面删除
                        //则删除一项后后面的项对弈的index都将变化。
          for j:=i-1 downto 0 do
            if(listbox1.Selected[j]=True) then
                        listBox1.Items.Delete(j);
          end;
      end;
end;
end.