BEGIN_MESSAGE_MAP(CShowDlg, CDialogEx)
END_MESSAGE_MAP()


// CShowDlg 消息处理程序


void CShowDlg::PostNcDestroy()
{
    // TODO: 在此添加专用代码和/或调用基类
    delete this;

    CDialogEx::PostNcDestroy();
}


BOOL CShowDlg::OnInitDialog()
{
    CDialogEx::OnInitDialog();

    // TODO:  在此添加额外的初始化
    CString strIPAddress;
    UINT uPort;
    m_pClientSocket->GetPeerName(strIPAddress,uPort);
    //CString strIPAddr = TEXT("127.0.0.1");
    //UINT uPort = 1234;

    CString strT;
    strT.Format(_T("\\\\%s:%d"), strIPAddress, uPort);
    SetWindowText(strT);

    return TRUE;  // return TRUE unless you set the focus to a control
    // 异常: OCX 属性页应返回 FALSE
}

// CShowDlg.cpp: 实现文件
//
#include "pch.h"
#include "Server.h"
#include "afxdialogex.h"
#include "CShowDlg.h"
#include "CClientSocket.h"
// CShowDlg 对话框

IMPLEMENT_DYNAMIC(CShowDlg, CDialogEx)

CShowDlg::CShowDlg(CClientSocket* pClientSocket, CWnd* pParent /*=nullptr*/) : CDialogEx(IDD_SHOW_DLG, pParent)
{
    m_pClientSocket = pClientSocket;
}

CShowDlg::~CShowDlg()
{
}

void CShowDlg::DoDataExchange(CDataExchange* pDX)
{
    CDialogEx::DoDataExchange(pDX);
}


BEGIN_MESSAGE_MAP(CShowDlg, CDialogEx)
END_MESSAGE_MAP()


// CShowDlg 消息处理程序

麻烦看一看

这次对了，谢谢了！！