为什么DEVC++会报错（网上的代码）

#include <windows.h>
#include <cstring>
#include <string>
using namespace std;
 
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
  WNDCLASSEX wc;
  HWND hwnd, hwndDT;
  MSG msg;
  RECT rect;
  int dtWidth,dtHeight;
 
  memset(&wc,0,sizeof(wc));
  wc.cbSize    = sizeof(WNDCLASSEX);
  wc.lpfnWndProc   = WndProc;
  wc.hInstance   = hInstance;
  wc.hCursor     = LoadCursor(NULL, IDC_ARROW);
  
  wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
  wc.lpszClassName = "WindowClass";
  wc.hIcon     = LoadIcon(NULL, IDI_APPLICATION);
  wc.hIconSm     = LoadIcon(NULL, IDI_APPLICATION);
 
  if(!RegisterClassEx(&wc)) {
    MessageBox(NULL, "Window Registration Failed!","Error!",MB_ICONEXCLAMATION|MB_OK);
    return 0;
  }
 
  hwndDT=GetDesktopWindow(); //取桌面句柄 
  GetWindowRect(hwndDT,&rect); //取桌面范围 
  dtWidth=rect.right-rect.left; //桌面宽度 
  dtHeight=rect.bottom-rect.top; //桌面高度 
  
  hwnd = CreateWindowEx(WS_EX_CLIENTEDGE,wc.lpszClassName,
    "First Windows Appliction",WS_VISIBLE|WS_OVERLAPPEDWINDOW,
    (dtWidth-640)/2,   /*窗体居中*/ 
    (dtHeight-480)/2,
    640,
    480,
    NULL,NULL,hInstance,NULL);
  //MoveWindow(hwnd, (width-640)/2, (height-480)/2, 640, 480, FALSE);
     
  if(hwnd == NULL) {
    MessageBox(NULL, "Window Creation Failed!","Error!", MB_ICONEXCLAMATION|MB_OK);
    return 0;
  }
 
  while(GetMessage(&msg, NULL, 0, 0) > 0) { 
    TranslateMessage(&msg);
    DispatchMessage(&msg);
  }
 
  return msg.wParam;
}
 
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
  HDC           hdc;
  PAINTSTRUCT   ps;
  RECT      rect;
  POINT     mouse;
  static int    cxChar, cyChar;
  static int    mX, mY;
  static HWND   hwndButton;
  static HWND   hwndEditbox;
  string      strXy;
  char      x[5], y[5];
  char      buff[4096] = {0};
  const int   IDcmdButton = 1;
  const int   IDeditBox = 2;
  
  cxChar = LOWORD(GetDialogBaseUnits());
  cyChar = HIWORD(GetDialogBaseUnits());
     
  switch (message) {
    case WM_CREATE:
      hwndButton = CreateWindow ( TEXT("button"), TEXT("Command Button"),
                                  WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
                                      cxChar * 6, cyChar * 15,
                                      30 * cxChar, 2.5 * cyChar,
                                      hwnd, (HMENU)IDcmdButton, ((LPCREATESTRUCT) lParam)->hInstance, NULL);
      if (!hwndButton) MessageBox(NULL,"创建按钮失败","Message",MB_OK|MB_ICONERROR);
      ShowWindow(hwndButton,SW_SHOW);
            UpdateWindow(hwndButton);
        
            hwndEditbox = CreateWindow( TEXT("edit"),NULL,
                    WS_CHILD | WS_VISIBLE | WS_BORDER | ES_MULTILINE,
                                      cxChar * 31, cyChar * 0.5,
                                      30 * cxChar, 9.5 * cyChar,
                    hwnd,(HMENU)IDeditBox,NULL,NULL);
                    
      if (!hwndEditbox) MessageBox(NULL,"创建文本框失败","Message",MB_OK|MB_ICONERROR);
      ShowWindow(hwndEditbox,SW_SHOW);
            UpdateWindow(hwndEditbox);
          return 0 ;
            
      case WM_PAINT:
      hdc = BeginPaint (hwnd, &ps);
        SetRect(&rect, 10, 10, 300, 200);
          FrameRect(hdc, &rect, (HBRUSH)GetStockObject(BLACK_BRUSH));
      GetClientRect (hwnd, &rect);
      rect.left += 20;
            rect.top += 2;
            //SetTextColor(hdc, RGB(255,0,0)); //可以用RGB三原色设置文本颜色
      DrawText(hdc, TEXT(" Hello, Dev-C++! "), -1, &rect, DT_SINGLELINE | DT_TOP | DT_LEFT);
      EndPaint(hwnd, &ps);
      return 0;
 
      case WM_SIZE:
      //GetWindowRect(hwnd, &rect);
      //MoveWindow(hwndButton, (rect.right-rect.left)/2 - 15*cxChar ,
      //(rect.bottom-rect.top)/2 - 1.25*cxChar, 30*cxChar, 2.5*cyChar, FALSE);
      return 0;
      
    case WM_COMMAND:
      //各控件的_click()事件 
      switch (LOWORD(wParam)) {
      case 0:
        PostQuitMessage(0);
        break;
      case IDcmdButton: 
        GetWindowText(hwndEditbox,buff,100);
        if (buff[0])
          MessageBox(NULL, buff, "ComandButton_Click()", MB_OK);
        else
          MessageBox(NULL, "激发ComandButton_Click()事件", "命令按钮", MB_ICONASTERISK);
        break;
      case IDeditBox:
        GetWindowText(hwndEditbox,buff,4096);
        break;
      }
      return 0; 
 
    case WM_LBUTTONDOWN: // WM_LBUTTONDOWN是鼠标左键按下的事件
      GetCursorPos(&mouse);
      GetWindowRect(hwnd, &rect);
      mX=mouse.x-rect.left;
      mY=mouse.y-rect.top;
      itoa(mX,x,10);
      itoa(mY,y,10);
      strXy="鼠标点击的窗体内坐标：("+string(x)+","+string(y)+")";
      SetWindowText(hwndEditbox,strXy.c_str());
      //MessageBox(NULL, strXy.c_str(), "", MB_ICONASTERISK);
      return 0;
 
    case WM_CLOSE:
      if (IDYES==MessageBox(hwnd, "是否真的要退出？", "确认", MB_ICONQUESTION | MB_YESNO))
        DestroyWindow(hwnd);  //销毁窗口
      return 0;
      
    case WM_DESTROY:
      ShellAbout(hwnd, "第一个窗口程序", "再见，期待您在评论区留言！", NULL);
      PostQuitMessage(0);
      return 0;
  }
  
  return DefWindowProc(hwnd, message, wParam, lParam);
}