Question

在线等，很急！！！【MFC中，局部函数如何修改控件变量？】

int32 CVICALLBACK EveryNCallback(TaskHandle taskHandle, int32 everyNsamplesEventType, uInt32 nSamples, void *callbackData)

{
CNIREADPCIDlg dlg;
int32 error = 0;
char errBuff[2048] = { '\0' };
static int totalRead = 0;
int32 read = 0;
float64 data[500] = { 0 };
CString cstrTipMessage;

/*********************************************/
// DAQmx Read Code
/*********************************************/
DAQmxErrChk(DAQmxReadAnalogF64(taskHandle, numSampsPerChan, 10.0, DAQmx_Val_GroupByScanNumber, data, sampsPerChanRead, &read, NULL)); //DAQmx_Val_GroupByChannel

if (read>0) {
cstrTipMessage.Format(_T("Acquired %d samples. Total %d\r"), (int)read, (int)(totalRead += read));
dlg.GetDlgItem(IDC_STATIC_READCOUNTER)->SetWindowTextW(_T("HHH"));
//SetDlgItemTextW(IDC_STATIC_READCOUNTER, cstrTipMessage);?????????
//AfxMessageBox(cstrTipMessage);
if (totalRead>100000&>askHandle != 0)
{
totalRead = 0;
/*********************************************/
// DAQmx Stop Code
/*********************************************/
DAQmxStopTask(gtaskHandle);
DAQmxClearTask(gtaskHandle);
}
fflush(stdout);
}
return 0;
}

上面为MFC的回调函数，进行数据采集，怎么将 SetDlgItemTextW(..., cstrTipMessage);在这个全局函数中使用？？？
很急，请大神赐教！

Answer 1

你这里有个dlg，如果这行正确的话，那下面加上也应该可以

dlg.GetDlgItem(IDC_STATIC_READCOUNTER)->SetWindowTextW(_T("HHH"));

// dlg..

dlg.SetDlgItemTextW(IDC_STATIC_READCOUNTER, cstrTipMessage);

追问

　　关键这一行也不正确！不过已经找到方法了
　　CNIREADPCIDlg* pdlg = (CNIREADPCIDlg*)(AfxGetApp()->m_pMainWnd);
　　按这种写法来做，就能够访问到控件了。

追答

嗯，赞！