为什么弹出关于对话框后，小弟我的编辑框就不能接收输入了

为什么弹出关于对话框后，我的编辑框就不能接收输入了？
#include <windows.h>
#include <iostream>
#include <fstream>
#include <string>
using   namespace   std;
#include   "resource.h "
static   HWND   hEdit;
LRESULT   CALLBACK   WndProc
(   HWND   hwnd,
  UINT   uMsg,
  WPARAM   wParam,
  LPARAM   lParam
  );
LRESULT   CALLBACK   WndEditProc
(   HWND   hwnd,
  UINT   uMsg,
  WPARAM   wParam,
  LPARAM   lParam
  );
WNDPROC   EditOldProc;
int   WINAPI   WinMain(HINSTANCE   hInstance,
      HINSTANCE   hPrevInstance,
      LPSTR   lpCmdLine,
      int   nCmdShow
      )
{
WNDCLASS   wc;
wc.cbClsExtra=0;
wc.cbWndExtra=0;
wc.hbrBackground=(HBRUSH)::GetStockObject(COLOR_BTNFACE);
wc.hCursor=::LoadCursor(NULL,IDC_ARROW);
wc.hInstance=hInstance;
wc.lpfnWndProc=WndProc;
wc.lpszClassName=TEXT( "EmhPod ");
wc.lpszMenuName=MAKEINTRESOURCE(IDR_MENU1);
wc.hIcon   =   LoadIcon   (hInstance,   MAKEINTRESOURCE(IDI_ICON1));
wc.style=CS_HREDRAW   |   CS_VREDRAW;
if(!RegisterClass(&wc))
{
::MessageBox(NULL,TEXT( "窗口注册失败 "),TEXT( "提示 "),MB_OK);
}
HWND   hwnd=::CreateWindow(TEXT( "EmhPod "),TEXT( "超级记事本1.0版 "),WS_OVERLAPPEDWINDOW   ,
                                                CW_USEDEFAULT,   CW_USEDEFAULT,
                                                  CW_USEDEFAULT,   CW_USEDEFAULT,
                                                NULL,   NULL,   hInstance,   NULL)   ;

::ShowWindow(hwnd,nCmdShow);
::UpdateWindow(hwnd);
MSG   msg;
while(GetMessage(&msg,NULL,0,0))
{
TranslateMessage   (&msg)   ;
DispatchMessage   (&msg)   ;
}
return   msg.wParam;
}
LRESULT   CALLBACK   WndProc
(   HWND   hwnd,
  UINT   uMsg,
  WPARAM   wParam,
  LPARAM   lParam
  )
{
HDC   hdc;
PAINTSTRUCT   ps;
RECT   rc;
RECT   rcEdit;
OPENFILENAME   ofn;               //   common   dialog   box   structure
char   szFile[260];               //   buffer   for   file   name
HANDLE   hf;                             //   file   handle

//   Initialize   OPENFILENAME
ZeroMemory(&ofn,   sizeof(ofn));
ofn.lStructSize   =   sizeof(ofn);
ofn.hwndOwner   =   hwnd;
ofn.lpstrFile   =   szFile;
//
//   Set   lpstrFile[0]   to   '\0 '   so   that   GetOpenFileName   does   not  
//   use   the   contents   of   szFile   to   initialize   itself.