编写的windows小程序运行后一闪而过，帮忙解决一下,该如何解决

编写的windows小程序运行后一闪而过，帮忙解决一下
写了一个小程序，可是运行时居然一闪而过，大家帮忙解决一下。

EditBoxDemo.c:

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "EditBoxDemo.h "


HWND           hEditItem,hEditResult,
                  hButtonAdd,hButtonReset,hButtonCancel,
  hStatic1,hStatic2;

HINSTANCE     hInst;
char   lpszAddItem[]   =   " ";
char   lpszResult[]     =   " ";
char     *stop;
long   nAddItem,nResult;
int     nMax;


LRESULT   CALLBACK   WndProc(HWND,UINT,WPARAM,LPARAM);

int   WINAPI   WinMain(
      HINSTANCE   hInstance,
      HINSTANCE   hPrevInst,
      LPSTR   lpszCmdLine,
      int   nCmdShow
      )

{
HWND   hwnd;
MSG   Msg;
WNDCLASS   wndclass;
char   lpszClassName[]   =   "编辑框 ";
char   lpszTitle[]   =   "编辑框示例－加法器 ";

wndclass.style   =   0;
wndclass.lpfnWndProc   =   WndProc;
wndclass.cbClsExtra   =   0;
        wndclass.cbWndExtra   =   0;
wndclass.hInstance   =   hInstance;
wndclass.hIcon   =   LoadIcon(NULL,IDI_APPLICATION);
wndclass.hCursor   =   LoadCursor(NULL,IDC_ARROW);
wndclass.hbrBackground   =   GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName   =   NULL;
wndclass.lpszClassName   =   lpszClassName;

if(!RegisterClass(&wndclass))
{
MessageBeep(0);
return   0;
}

hwnd   =   CreateWindow(
lpszClassName,
lpszTitle,
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL
);
ShowWindow(hwnd,nCmdShow);
UpdateWindow(hwnd);
while(GetMessage(&Msg,NULL,0,0))
{
TranslateMessage(&Msg);
DispatchMessage(&Msg);
}

return   Msg.wParam;
}

LRESULT   CALLBACK   WndProc(
  HWND   hwnd,
  UINT   message,
  WPARAM   wParam,
  LPARAM   lParam
  )
{

switch(message)
{
case   WM_CREATE:
hStatic1   =   CreateWindow
( "STATIC ",
  "加数： ",
  WS_CHILD|WS_VISIBLE,
  40,20,
  50,20,
  hwnd,
  (HMENU)IDS_1,
  hInst,
  NULL);
hStatic2   =   CreateWindow
( "STATIC ",
"结果： ",
WS_CHILD|WS_VISIBLE,
40,70,
50,20,
hwnd,
(HMENU)IDS_2,
hInst,
NULL);
hEditItem   =   CreateWindow
( "EDIT ",
NULL,
WS_CHILD|WS_VISIBLE|ES_LEFT|WS_BORDER,
130,20,
80,20,
hwnd,
(HMENU)IDE_ADDITEM,
hInst,
NULL);
hEditResult=   CreateWindow
( "EDIT ",
NULL,
WS_CHILD|WS_VISIBLE|ES_LEFT|WS_BORDER|ES_READONLY,
130,70,
80,20,
hwnd,
(HMENU)IDE_RESULT,