为防止系统进入空闲模式,您可以尝试使用
SetThreadExecutionState功能.该函数通知系统应用程序正在使用,并允许您指定线程的执行要求.用法可以这样,但我不知道这是否也会影响磁盘掉电定时器：
- type
- EXECUTION_STATE = DWORD;
- const
- ES_SYSTEM_required = $00000001;
- ES_DISPLAY_required = $00000002;
- ES_USER_PRESENT = $00000004;
- ES_AWAYMODE_required = $00000040;
- ES_CONTINUOUS = $80000000;
- function SetThreadExecutionState(esFlags: EXECUTION_STATE): EXECUTION_STATE;
- stdcall; external 'kernel32.dll' name 'SetThreadExecutionState';
- procedure TForm1.Button1Click(Sender: TObject);
- begin
- if SetThreadExecutionState(ES_CONTINUOUS or ES_SYSTEM_required or
- ES_AWAYMODE_required) <> 0 then
- try
- // execute your long running task here
- finally
- SetThreadExecutionState(ES_CONTINUOUS);
- end;
- end;
或者也可以使用为Windows 7设计的新功能PowerCreateRequest,PowerSetRequest和PowerClearRequest,但是文档令人困惑,我目前还没有找到任何使用示例.
或者您可以使用GUID_DISK_SUBGROUP电源设置子组修改PowerWriteACValueIndex或PowerWriteDCValueIndex功能的电源设置.
