系统设备变化,系统向应用程序发出WM_DEVICECHANGE消息,应用程序注册一个消息处理函数,来获取设备变化通知.
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, AppEvnts, ExtCtrls, StdCtrls;
type
TForm1 = class(TForm)
Label1: TLabel;
private
{ Private declarations }
procedure WMDeviceChange(var Msg: TMessage); message WM......
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