C++ win32 async socket client send() issue

我必须编写一个WIN32，异步套接字客户端应用程序，它连接到服务器。我可以启动程序，连接到服务器，接收并处理接收到的数据，但是当我试图向服务器发送消息时，服务器上什么也没有发生。我没有任何套接字错误消息，并且send()函数返回正确的发送字节。但是服务器看起来好像没有接收到任何东西。我的send()是在FD_READ语句中调用的，首先是if语句。我试图将其移动到其他语句(WM_CREATE, FD_WRITE, FD_CONNECT)，但仍然是同样的问题。我试图找到什么是错的，看了很多很多论坛，因为一个月，但我没有发现问题。任何帮助都将非常感激。下面是我的代码示例(我跳过了不有趣的部分):

#include <windows.h>
#include <fstream>
#include <sstream>
#include<process.h>
#pragma comment(lib,"ws2_32.lib")
using namespace std;
#define IDC_BUTTON_CONNECT 101 // Button identifiers
#define IDC_EDIT_IP 102 // Edit / Text box identifiers
#define IDC_EDIT_PORT 103
#define IDC_EDIT_DEBUG 104
#define WM_SOCKET 105 // Socket messages structure identifier
HWND hWnd;
HWND hEditIp;
HWND hEditPort;
HWND hDebug;
HWND hButtonConnect;
HANDLE hReadMutex;
SOCKET Socket = NULL;
SOCKADDR_IN SockAddr;
char *ip = "";
char *port = "";
bool connectStatus = FALSE;
char readBuffer[5000];
char id[32];
char version[256];
LPSTR statusText = TEXT("Connecting...");
LRESULT CALLBACK WinProc(HWND hWnd,UINT message,WPARAM wParam,LPARAM lParam);
// WinMain...
// appendTextToEdit function...
// incoming data processing thread (not used yet)...
LRESULT CALLBACK WinProc(HWND hWnd,UINT msg,WPARAM wParam,LPARAM lParam)
{   
    switch(msg)
    {
        case WM_CREATE:
        {
        // Get IP and port from file "config.ini"...        
        //Create windows for IP, Port and Debug...
        // Create "connect" button...

        WSADATA WsaDat; // Winsock initialization...
        int nResult=WSAStartup(MAKEWORD(2,2),&WsaDat);
        if(nResult!=0)
        {
            statusText=TEXT("Winsock initialization failed");                   
            InvalidateRect(hWnd, NULL, TRUE);
            break;
        }
        Socket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); // Creating socket...
        if(Socket==INVALID_SOCKET)
        {
            statusText=TEXT("Socket creation failed");                  
            InvalidateRect(hWnd, NULL, TRUE);
            break;
        }
        nResult=WSAAsyncSelect(Socket,hWnd,WM_SOCKET,(FD_CLOSE|FD_READ|FD_WRITE|FD_CONNECT)); // Select AsyncSocket events...
        if(nResult)
        {
            statusText=TEXT("WSAAsyncSelect failed");                   
            InvalidateRect(hWnd, NULL, TRUE);
            break;
        }           
        // Set up our socket address structure...
        SockAddr.sin_addr.s_addr=inet_addr(ip);
        SockAddr.sin_port=htons(atoi(port)); 
        SockAddr.sin_family=AF_INET;        
        connect(Socket,(LPSOCKADDR)(&SockAddr),sizeof(SockAddr)); // Connexion command              
    }
    break;
    case WM_PAINT:
    {
        // painting / updating the window...
    }
    break;
    case WM_COMMAND:
        switch(LOWORD(wParam))
        {
            case IDC_BUTTON_CONNECT:
            {                   
                if(connectStatus==FALSE) // Avoid to reconnect when already online...
                {
                    // Window repaint with updated text (statusText = global variable)
                    statusText=TEXT("Connecting...");                   
                    InvalidateRect(hWnd, NULL, TRUE);                   
                    // Retrieve edit box datas and store to variables and file...
                    // Saving data to "config.ini" file...
                    // Reinitializing adress structure with new host adress and port from edit boxes, and reconnect attempt...
                    SockAddr.sin_addr.s_addr=inet_addr(ip);
                    SockAddr.sin_port=htons(atoi(port));
                    SockAddr.sin_family=AF_INET;    
                    connect(Socket,(LPSOCKADDR)(&SockAddr),sizeof(SockAddr));
                }
                break;
            }
            break;          
        }
        break;          
    case WM_SOCKET:
    {           
        switch(WSAGETSELECTEVENT(lParam))
        {
            case FD_CONNECT:
            {
                connectStatus = TRUE;
                statusText=TEXT("Connected");               
            }
            case FD_READ:
            {
                appendTextToEdit(hDebug, "FD_READ event...n");
                char *rawVariable = nullptr;                    
                char *next_token = nullptr;                         
                recv(Socket, readBuffer, sizeof(readBuffer), 0);            
                rawVariable = readBuffer;               
                if(strstr(rawVariable, "id=") != NULL) // Identifying message sent by the server (starts with id, version, ...) and store the values to variables (working fine)
                {   
                    char *label = strtok_s(rawVariable, "=", &next_token);
                    char *pId = strtok_s(NULL, "n", &next_token);  
                    rawVariable = strtok_s(NULL, "", &next_token);
                    strcpy_s(id, pId);
                    char message[256] = "Qh57=1"; // Setting up message structure... (the server should do an action when it receives "Qh57=1rn" but it doesn't...) here is my problem...
                    appendTextToEdit(hDebug, "Message sent : ");
                    appendTextToEdit(hDebug, message);
                    char *endline = "rn";
                    strcat_s(message, endline); 
                    string messageString(message);          
                    int messageLength = ((messageString.length()) - 2); // Get outgoing string length (-2)                          
                    int sent = send(Socket, message , messageLength , 0);               
                    char buffer [33]; // Display number of bytes sent...
                    _itoa_s(sent,buffer,10);                    
                    appendTextToEdit(hDebug, " (");
                    appendTextToEdit(hDebug, buffer);
                    appendTextToEdit(hDebug, " bytes sent)n");
                }
                if( strstr(rawVariable, "version") != NULL)
                {
                    char *label = strtok_s(rawVariable, "=", &next_token);      
                    char *pVersion = strtok_s(NULL, "n", &next_token); 
                    rawVariable = strtok_s(NULL, "", &next_token);      
                    strcpy_s(version, pVersion);    
                }                                       
                appendTextToEdit(hDebug, "End of FD_READn");           
            }
            break;
            case FD_WRITE:
            {
                appendTextToEdit(hDebug, "FD_WRITE event...n");
                appendTextToEdit(hDebug, "End of FD_WRITEn");
            }
            break; 
            case FD_CLOSE:
            {   
                statusText = "Disconnected from server";
                connectStatus = FALSE;
                InvalidateRect(hWnd, NULL, TRUE);
//              SendMessage(hWnd, WM_DESTROY, NULL, NULL); // Final version...                  
            }
            break;
        }
        break; 
    }
    break;
    case WM_DESTROY:
    {
        closesocket(Socket);
        WSACleanup();
        PostQuitMessage(0);
        return 0;
    }
    break;
}   
return DefWindowProc(hWnd,msg,wParam,lParam);
}