关于使用RichEdit控件的有关问题

关于使用RichEdit控件的问题
我在RichEdit中插入一张图片，然后调用下面的代码
CComPtr<IRichEditOle> pRichEditOle;
SendMessage(m_hWnd/*RichEidt窗口句柄*/, EM_GETOLEINTERFACE, 0, (LPARAM)&pRichEditOle);
CComPtr<ITextRange> pRichRange;
CComQIPtr<ITextDocument>(pRichEditOle)->Range(0, 0, &pRichRange);
if (NULL == pRichRange)
  return E_FAIL;
pRichRange->Endof(tomStory, 1, NULL);
CComBSTR bstrText;
pRichRange->GetText(bstrText);

我插入一张图片，但调用GetText也有内容返回，输出内容来看时是下面的值
"?\r\n"或者是"?\n",我的问题是怎么可以判断RichEdit窗口那里有没有文字存在,因为我只插入一张
图片到RichEdit控件中，我希望调用GetText应该没有文字返回.

------解决方案--------------------
// My callback procedure that writes the rich edit control contents
// to a file.
static DWORD CALLBACK 
MyStreamOutCallback(DWORD dwCookie, LPBYTE pbBuff, LONG cb, LONG *pcb)
{
CFile* pFile = (CFile*) dwCookie;

pFile->Write(pbBuff, cb);
*pcb = cb;

return 0;
}

// The example code.

// The file to store the contents of the rich edit control.
CFile cFile(TEXT("My_RichEdit_OutFile.rtf"), 
CFile::modeCreate|CFile::modeWrite);
EDITSTREAM es;

es.dwCookie = (DWORD) &cFile;
es.pfnCallback = MyStreamOutCallback; 
m_myRichEditCtrl.StreamOut(SF_RTF, es);
来自msdn，仅供参考，查找CRichEditCtrl就可以找到