Why can't my communication thread use the CSokcet global variable of the main thread

falconwbgjdl

In CMyDialog:
CSocket m_pSocket;
CMyThread m_pThread;

In CMyDialog :: InitDialog ()

m_pSocket = new CSocket ();
m_pSocket-> Create (MYPORT);
... Socket generation is perfectly fine

m_pThread = AfxBeginThread (RUNTIME_CLASS (CMyThread)); The establishment of Thread is also no problem at all

In CMyDialog :: OnMyButtonClick ()
m_pThread-> PostThreadMessage (MYMESSAGE);

In the CMyThread message loop:

case MYMESSAGE:
   (This is a CMyDlg class global variable generated when the Thread is initialized)
    m_pDlg-> RecvData ();

Everything was fine before:
But when m_pThread executes CMyDlg :: RecvData ()
CMyDlg :: RecvData () ｛
m_pSocket-> send (...) Here m_pSocket == 0, there is no problem if you use this-> RecvData () without going through the thread, why?
Does the CSocket class have a dependency on its spawning thread?

深蓝旅者

MFC objects are thread specifical, you need to do Detach / Attach, you can find more detail in the following post.

rws1989318

CSocket is not thread-safe, it must rely on a window main thread