struct结构问题？

void CFileView::OnGetDispInfo(NMHDR* pNMHDR, LRESULT* pResult)
{
CString string;
LV_DISPINFO* pDispInfo = (LV_DISPINFO*) pNMHDR;
}
两个结构体可以转换？？？？那通过指针转换后的数据会出问题吗？typedef struct tagNMHDR {
    HWND hwndFrom;
    UINT_PTR idFrom;
    UINT code;
} NMHDR;typedef   struct   tag   LV_DISPINFO   {
  NMHDR   hdr;
  LV_ITEM   item;
  }   LV_DISPINFO;