在 c# 中处理另一个 class 的按钮逻辑问题

Question

在我的程序中我现在有 2 个 classes 它最终会随着更多的 classes 而增长，第一个 class 是我的主要 class windows 表单，其中包含所有按钮和文本等。现在在我的主表单中，我有一个名为关闭连接的按钮，单击该按钮时，循环将从第二个 class 结束。我遇到的问题是如何完成能够从我的主 class.

按钮关闭该循环

这是主要的class代码

using System;
using System.Windows.Forms;

namespace BarcodeReceivingApp
{



    //TelnetConnection stopConnection = new TelnetConnection();
    public partial class BarcodeReceivingForm : Form
    {
        //GLOBAL VARIABLES
        private const string Hostname = "myip";
        private const int Port = 23;


        public BarcodeReceivingForm()
        {
            InitializeComponent();

            //FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
            WindowState = FormWindowState.Maximized;
        }

        private void btn_ConnectT_Click(object sender, EventArgs e)
        {
            var readData = new TelnetConnection(Hostname, Port);
            readData.ServerSocket(Hostname, Port, this);
        }

        private void btn_StopConnection_Click(object sender, EventArgs e)
        {
            var connection = new TelnetConnection(Hostname, Port);
            connection.CloseConnection();
        }

        private void btn_RemoveItemFromListAt_Click(object sender, EventArgs e)
        {
            for (var i = lst_BarcodeScan.SelectedIndices.Count - 1; i >= 0; i--)
            {
                lst_BarcodeScan.Items.RemoveAt(lst_BarcodeScan.SelectedIndices[i]);
            }
        }

        private void BarcodeReceivingForm_Load(object sender, EventArgs e)
        {
            lst_BarcodeScan.SelectionMode = SelectionMode.MultiSimple;
        }

        private void btn_ApplicationSettings_Click(object sender, EventArgs e)
        {
            var bcSettingsForm = new BarcodeReceivingSettingsForm();
            bcSettingsForm.Show();
        }
    }
}

第二个 class 代码，其中大部分逻辑是在 ReadWrite() 方法中，我需要在 stopconnection 中放置例如 button.click 然后中断循环并关闭端口 23 连接，这部分我在关闭连接方法中完成了我在之后调用while 循环。现在写我有命令变量=退出然后打破循环但我不想成为我想要按钮这样做的原因

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Sockets;
using System.Runtime.Remoting.Messaging;
using System.Security.Authentication.ExtendedProtection;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace BarcodeReceivingApp
{
    public class TelnetConnection
    {
        private Thread _readWriteThread;
        private TcpClient _client;
        private NetworkStream _networkStream;
        private string _hostname;
        private int _port;
        private BarcodeReceivingForm _form;

        public TelnetConnection(string hostname, int port)
        {
            this._hostname = hostname;
            this._port = port;
        }

        public TelnetConnection()
        {

        }

        public void ServerSocket(string ip, int port, BarcodeReceivingForm f)
        {
            this._form = f;
            try
            {
                _client = new TcpClient(ip, port);
            }
            catch (SocketException)
            {
                MessageBox.Show(@"Failed to connect to server");
                return;
            }

            _networkStream = _client.GetStream();
            _readWriteThread = new Thread(ReadWrite);
            //_readWriteThread = new Thread(() => ReadWrite(f));
            _readWriteThread.Start();
        }


        public void ReadWrite()
        {           
            while (true)
            {
                var command = "";
                if (command == "Exit")
                    break;

                var received = Read();

                if (_form.lst_BarcodeScan.InvokeRequired)
                {
                    _form.lst_BarcodeScan.Invoke(new MethodInvoker(delegate { _form.lst_BarcodeScan.Items.Add(received + Environment.NewLine); }));
                }
            }

            CloseConnection();
        }

        public string BarcodeRead()
        {
            var reading = Read();

            return reading;
        }

        public string Read()
        {
            var data = new byte[1024];
            var received = "";

            var size = _networkStream.Read(data, 0, data.Length);
            received = Encoding.ASCII.GetString(data, 0, size);

            return received;
        }

        public void CloseConnection()
        {
            Console.WriteLine(@"Closed Connection");
            _networkStream.Close();
            _client.Close();
        }
    }
}

此外，我一直在 google 上搜索，也在 stack overflow 上搜索类似问题的内容，但我找不到任何可以解决我的问题的内容。

Answer 1

您应该将循环更改为在布尔条件更改时自动停止。您可以在这里做一个小改动。您将需要创建一个新方法来调用关闭并稍微更改 ReadWrite 方法

private bool isExiting = false;
public void Exit()
{
    isExiting = true;
}

 public void ReadWrite()
 {           
     do
     {     
         var received = Read();

         if (_form.lst_BarcodeScan.InvokeRequired)
         {
             _form.lst_BarcodeScan.Invoke(new MethodInvoker(delegate { _form.lst_BarcodeScan.Items.Add(received + Environment.NewLine); }));
         }
     } while (!isExiting)

     CloseConnection();
 }

现在调用 connection.Exit(); 将关闭所有内容但是您仍然有问题。您没有在连接表单中保留 class 的实例。在表单中，您需要更改连接和关闭以使用相同的对象。这是两种方法的小改动

    private TelnetConnection connection;
    private void btn_ConnectT_Click(object sender, EventArgs e)
    {
        connection = new TelnetConnection(Hostname, Port);
        connection.ServerSocket(Hostname, Port, this);
    }

    private void btn_StopConnection_Click(object sender, EventArgs e)
    {
        connection.Exit();
    }

现在他们都使用同一个对象，所以它应该可以正常工作。

Answer 2

NetworkStream.Read() returns 0 当套接字关闭时，您可以使用它来跳出循环。所以 return 当读取 returns 0.

时为 null

public string Read()
{
    var data = new byte[1024];
    var received = "";

    var size = _networkStream.Read(data, 0, data.Length);
    if(size == 0)
        return null;

    received = Encoding.ASCII.GetString(data, 0, size);

    return received;
}

并在您的 ReadWrite 方法中

public void ReadWrite()
{           
    while (true)
    {
        var command = "";
        if (command == "Exit")
            break;

        var received = Read();
        if(received == null)
            break;

        if (_form.lst_BarcodeScan.InvokeRequired)
        {
        _form.lst_BarcodeScan.Invoke(new MethodInvoker(delegate { _form.lst_BarcodeScan.Items.Add(received + Environment.NewLine); }));
        }
    }

    CloseConnection();
}

在 c# 中处理另一个 class 的按钮逻辑问题

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c#-4.0