C语言程序

#include "stdafx.h"
#include <windows.h>
#include <windowsx.h>
#include "resource.h"
#include "MainDlg.h"
#include <stdlib.h>


BOOL WINAPI Main_Proc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    switch(uMsg)
    {
        HANDLE_MSG(hWnd, WM_INITDIALOG, Main_OnInitDialog);
        HANDLE_MSG(hWnd, WM_COMMAND, Main_OnCommand);
HANDLE_MSG(hWnd,WM_CLOSE, Main_OnClose);
    }


    return FALSE;
}


BOOL Main_OnInitDialog(HWND hwnd, HWND hwndFocus, LPARAM lParam)
{
    return TRUE;
}


void Main_OnCommand(HWND hwnd, int id, HWND hwndCtl, UINT codeNotify)
{
if (IDC_CLOSE == id)
{
Main_OnClose(hwnd);
}


if (IDC_BUTTON1 == id)
{
TCHAR n1[64];
GetWindowText(GetDlgItem(hwnd,IDC_EDIT1),n1,sizeof(n1));


if (0 == strlen(n1)) //加数1是否为空
{
MessageBox(hwnd,TEXT("加数1不能为空，请重新输入！"),TEXT("警告"),MB_OK);
return;
}
/*MessageBox(hwnd,n1,TEXT("1111"),MB_OK);*/
TCHAR n2[64];
GetWindowText(GetDlgItem(hwnd,IDC_EDIT2),n2,sizeof(n2));
if (0 == strlen(n2)) //加数1是否为空
{
MessageBox(hwnd,TEXT("加数2不能为空，请重新输入！"),TEXT("警告"),MB_OK);
return;
}


int d1=atoi(n1);
int d2=atoi(n2);
int ret=d1+d2;
TCHAR j[128];
wsprintf(j,"%i",ret);
SetWindowText(GetDlgItem(hwnd,IDC_EDIT3),j);
}

}


void Main_OnClose(HWND hwnd)
{
    EndDialog(hwnd, 0);
}