【C++代码】
#include <tchar.h>
#include <stdio.h>
#include <Windows.h>
#include <CommCtrl.h>
#include "resource.h"

#pragma comment(lib, "ws2_32.lib")

#pragma comment(lib, "Comctl32.lib")
#pragma comment(linker, "\"/manifestdependency:type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"")

#define send_data(str) send(sock, str, strlen(str), NULL)

HWND hDlg;
SOCKET sock;
char *szPartA = "CMD_UART_";
char *szPartB = "_ENDUART_END";
BOOL bBeep = FALSE;

void connect()
{
    SOCKADDR_IN addr;
    sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    addr.sin_family = AF_INET;
    addr.sin_addr.S_un.S_addr = inet_addr("192.168.1.8");
    addr.sin_port = htons(1030);
    connect(sock, (SOCKADDR *)&addr, sizeof(addr));
}

void control_beep()
{
    char data[30] = "CMD_BUZZER_";
    if (bBeep)
        strcat_s(data, "0");
    else
        strcat_s(data, "1");
    bBeep = !bBeep;
    send(sock, data, strlen(data), NULL);
}

void showmsg(BOOL bShowContent = FALSE)
{
    char buffer[1024] = {0};
    int len = recv(sock, buffer, sizeof(buffer), NULL);
    buffer[len] = '\0';
    SetDlgItemTextA(hDlg, IDC_EDIT2, buffer);

    if (bShowContent)
    {
        int lenA = strlen(szPartA);
        int lenB = strlen(szPartB);
        int buf_len = strlen(buffer);
        buffer[buf_len - lenB] = '\0';
        SetDlgItemTextA(hDlg, IDC_EDIT3, buffer + lenA);
    }
}

void sendmsg()
{
    int lenA = strlen(szPartA);
    int lenB = strlen(szPartB);
    int len = lenA + lenB + 1;

    HWND hEdit = GetDlgItem(hDlg, IDC_EDIT1);
    int len_input = GetWindowTextLengthA(hEdit);
    len += len_input;
    char *str = new char[len];
    strcpy_s(str, len, szPartA);
    GetWindowTextA(hEdit, str + lenA, len + 1);
    strcat_s(str, len, szPartB);
   
    send_data(str);

    delete[] str;

    showmsg(TRUE);
}

void seticon()
{
    HICON hicon = LoadIcon(NULL, IDI_APPLICATION);
    SendMessage(hDlg, WM_SETICON, ICON_BIG, (LPARAM)hicon);
    SendMessage(hDlg, WM_SETICON, ICON_SMALL, (LPARAM)hicon);
}

void drawimg(LPDRAWITEMSTRUCT lpDis)
{
    FillRect(lpDis->hDC, &lpDis->rcItem, (HBRUSH)GetStockObject(WHITE_BRUSH));
}

INT_PTR CALLBACK DlgProc(HWND hDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    int wmId;
    switch (uMsg)
    {
    case WM_INITDIALOG:
        ::hDlg = hDlg;
        seticon();
        connect();
        return TRUE;
    case WM_COMMAND:
        wmId = LOWORD(wParam);
        switch (wmId)
        {
        case IDOK:
        case IDCANCEL:
            EndDialog(hDlg, wmId);
            break;
        case IDC_BUTTON1:
            control_beep();
            showmsg();
            break;
        case IDC_CHECK1:
        case IDC_CHECK2:
        case IDC_CHECK3:
            {
                int p = SendDlgItemMessage(hDlg, wmId, BM_GETCHECK, NULL, NULL);
                char str[30] = "CMD_LED_1_0";
                str[8] += wmId - IDC_CHECK1;
                str[10] += p;
                send(sock, str, strlen(str), NULL);
                showmsg();
            }
            break;
        case IDC_BUTTON2:
            sendmsg();
            break;
        case IDC_BUTTON3:
            send_data("CMD_READ_ALL_END");
            showmsg();
            break;
        }
        break;
    case WM_DESTROY:
        closesocket(sock);
        break;
    case WM_DRAWITEM:
        {
            LPDRAWITEMSTRUCT lpDis = (LPDRAWITEMSTRUCT)lParam;
            if (lpDis->CtlID == IDC_VIDEO)
                drawimg(lpDis);
        }
        break;
    }
    return FALSE;
}

int WINAPI _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow)
{
    WSADATA wsa;
    WSAStartup(MAKEWORD(2, 2), &wsa);
   
    INT_PTR rs = DialogBox(hInstance, MAKEINTRESOURCE(IDD_DIALOG1), NULL, DlgProc);

    WSACleanup();
    return rs;
}

【RC资源文件】
// Microsoft Visual C++ generated resource script.
//
#include "resource.h"

#define APSTUDIO_READONLY_SYMBOLS
/////////////////////////////////////////////////////////////////////////////
//
// Generated from the TEXTINCLUDE 2 resource.
//
#include "afxres.h"

/////////////////////////////////////////////////////////////////////////////
#undef APSTUDIO_READONLY_SYMBOLS

/////////////////////////////////////////////////////////////////////////////
// Chinese (Simplified, PRC) resources

#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_CHS)
LANGUAGE LANG_CHINESE, SUBLANG_CHINESE_SIMPLIFIED

#ifdef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//
// TEXTINCLUDE
//

1 TEXTINCLUDE
BEGIN
    "resource.h\0"
END

2 TEXTINCLUDE
BEGIN
    "#include ""afxres.h""\r\n"
    "\0"
END

3 TEXTINCLUDE
BEGIN
    "\r\n"
    "\0"
END

#endif    // APSTUDIO_INVOKED

#endif    // Chinese (Simplified, PRC) resources
/////////////////////////////////////////////////////////////////////////////


/////////////////////////////////////////////////////////////////////////////
// English (Australia) resources

#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENA)
LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_AUS

/////////////////////////////////////////////////////////////////////////////
//
// Dialog
//

IDD_DIALOG1 DIALOGEX 0, 0, 309, 257
STYLE DS_SETFONT | DS_MODALFRAME | DS_FIXEDSYS | DS_CENTER | WS_MINIMIZEBOX | WS_POPUP | WS_CAPTION | WS_SYSMENU
CAPTION "Wifi 测试"
FONT 8, "MS Shell Dlg", 400, 0, 0x1
BEGIN
    EDITTEXT        IDC_EDIT1,7,236,239,14,ES_AUTOHSCROLL
    DEFPUSHBUTTON   "发送",IDC_BUTTON2,252,236,50,14
    PUSHBUTTON      "蜂鸣器",IDC_BUTTON1,7,7,50,14
    PUSHBUTTON      "查看传感器状态",IDC_BUTTON3,195,7,67,14
    CONTROL         "LED1",IDC_CHECK1,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,270,7,32,10
    EDITTEXT        IDC_EDIT2,7,29,255,14,ES_AUTOHSCROLL | ES_READONLY
    CONTROL         "LED2",IDC_CHECK2,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,270,22,32,10
    EDITTEXT        IDC_EDIT3,7,47,255,14,ES_AUTOHSCROLL | ES_READONLY
    CONTROL         "LED3",IDC_CHECK3,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,270,39,32,10
    CONTROL         "",IDC_VIDEO,"Static",SS_OWNERDRAW,7,64,295,169
END


/////////////////////////////////////////////////////////////////////////////
//
// DESIGNINFO
//

#ifdef APSTUDIO_INVOKED
GUIDELINES DESIGNINFO
BEGIN
    IDD_DIALOG1, DIALOG
    BEGIN
        LEFTMARGIN, 7
        RIGHTMARGIN, 302
        TOPMARGIN, 7
        BOTTOMMARGIN, 250
    END
END
#endif    // APSTUDIO_INVOKED

#endif    // English (Australia) resources
/////////////////////////////////////////////////////////////////////////////



#ifndef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//
// Generated from the TEXTINCLUDE 3 resource.
//


/////////////////////////////////////////////////////////////////////////////
#endif    // not APSTUDIO_INVOKED

【资源头文件】
//{{NO_DEPENDENCIES}}
// Microsoft Visual C++ generated include file.
// Used by WifiConnect.rc
//
#define IDD_DIALOG1                     101
#define IDC_BUTTON1                     1001
#define IDC_CHECK1                      1002
#define IDC_CHECK2                      1003
#define IDC_CHECK3                      1004
#define IDC_EDIT1                       1005
#define IDC_BUTTON2                     1006
#define IDC_EDIT2                       1007
#define IDC_EDIT3                       1008
#define IDC_BUTTON3                     1009
#define IDC_VIDEO                       1010

// Next default values for new objects
//
#ifdef APSTUDIO_INVOKED
#ifndef APSTUDIO_READONLY_SYMBOLS
#define _APS_NEXT_RESOURCE_VALUE        102
#define _APS_NEXT_COMMAND_VALUE         40001
#define _APS_NEXT_CONTROL_VALUE         1011
#define _APS_NEXT_SYMED_VALUE           101
#endif
#endif

【蜂鸣器测试】

【传感器状态】

CMD_LED_0_0_0_ENDLED_DHT11_0.0_0.0_ENDDHT11_BUZZER_0_ENDBUZZER_END

【用复选框控制LED灯的亮灭】

【发送和接收字符串】

老哥稳！