mainunit.pas

来自「Delphi7编程80例(完全版)」· PAS 代码 · 共 49 行

unit MainUnit;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, FileCtrl, ExtCtrls, JPEG;

type
  TMainForm = class(TForm)
    Button1: TButton;
    DriveComboBox1: TDriveComboBox;
    DirectoryListBox1: TDirectoryListBox;
    FileListBox1: TFileListBox;
    Image1: TImage;
    procedure Button1Click(Sender: TObject);
    procedure FileListBox1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

{$R *.DFM}

procedure TMainForm.Button1Click(Sender: TObject);
var
  sParam: PChar;
begin
  sParam:= PChar(FileListBox1.FileName);
  SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, sParam, SPIF_SENDWININICHANGE);
end;


procedure TMainForm.FileListBox1Click(Sender: TObject);
var S: String;
begin
  S:= UpperCase(ExtractFileExt(FileListBox1.FileName));
  if (S= '.BMP') or (S= '.JPEG')or (S= '.JPG') then
    Image1.Picture.LoadFromFile( FileListBox1.FileName);
end;

end.