Handle Key Down Events on Active CView

This blog will help the MFC developer to get the key press event using ON_WM_KEYDOWN() event handler.

Step 1

Add OnKeyDown method declaration in .h file of subclass of CView like as:           

afx_msg void OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags);

nChar

         Virtual key code of the given key. see Winuser.h

nRepCnt

         Repeat count.

nFlags

         Specifies the scan code, key-transition code, previous key state, and context code.

Step 2

Add ON_WM_KEYDOWN() in BEGIN_MESSAGE_MAP and END_MESSAGE_MAP in .m file of subclass of CView like as:        

BEGIN_MESSAGE_MAP(CDrawViewView, CView)
        ON_WM_KEYDOWN()
        END_MESSAGE_MAP()

Here , CDrawViewView is a subclass of CView.
 

Step 3

Add OnKeyDown event definition in .m file like as:        

/* Key Down Events */
void CDrawViewView::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
      switch (nChar)
      {
             case VK_DELETE:
                   AfxMessageBox(L"Delete Key Pressed");
                   break;
             default:
                   CView::OnKeyDown(nChar, nRepCnt, nFlags);
      }
}

In above method , get delete key event and showing message box with text "Delete Key Pressed". And VK_DELETE define in winuser.h.