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如果用户在未输入任何输入的情况下单击连接，如何添加显示必须输入的异常？如果用户在不输入名称、IP 和端口的情况下单击连接按钮，我希望显示一个消息框。[解决了]

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net.Sockets;
using System.Threading;

namespace SocketClient
{

    public partial class SocketClient : Form
    {
        System.Net.Sockets.TcpClient clientSocket = new System.Net.Sockets.TcpClient();
        NetworkStream serverStream = default(NetworkStream);
        string readData = null;


        public SocketClient()
        {
            InitializeComponent();
        }


        private void getMessage()
        {
            while (true)
            {
                serverStream = clientSocket.GetStream();
                int buffSize = 0;
                byte[] inStream = new byte[10025];
                buffSize = clientSocket.ReceiveBufferSize;
                serverStream.Read(inStream, 0, buffSize);
                string returndata = System.Text.Encoding.ASCII.GetString(inStream);
                readData = "" + returndata;
                msg();
            }
        }


        private void msg()
        {
            if (this.InvokeRequired)
                this.Invoke(new MethodInvoker(msg));
            else
                textDisplay.Text = textDisplay.Text + Environment.NewLine + " >> " + readData;
        }


        private void buttonConnect_Click(object sender, EventArgs e)
        {

            readData = "Conected to NYP Server ...";
            msg();
            //clientSocket.Connect("127.0.0.1", 8888);
            clientSocket.Connect(textIP.Text, Convert.ToInt32(textPort.Text));
            serverStream = clientSocket.GetStream();

            byte[] outStream = System.Text.Encoding.ASCII.GetBytes(textName.Text + "$");
            serverStream.Write(outStream, 0, outStream.Length);
            serverStream.Flush();

            Thread ctThread = new Thread(getMessage);
            ctThread.Start();
        }

        private void buttonSend_Click(object sender, EventArgs e)
        {
            // Show msg box if no server is connected
            if (serverStream == null)
            {
                MessageBox.Show("Please connect to a server first!");
                return;
            }

            // Send text
            byte[] outStream = System.Text.Encoding.ASCII.GetBytes(textSend.Text + "$");
            serverStream.Write(outStream, 0, outStream.Length);
            serverStream.Flush();

            // Clear text
            textSend.Text = "";

        }

        private void textDisplay_TextChanged(object sender, EventArgs e)
        {
            textDisplay.SelectionStart = textDisplay.Text.Length;
            textDisplay.ScrollToCaret();
            textDisplay.Refresh();
        }

        private void textSend_TextChanged(object sender, EventArgs e)
        {
            buttonSend.Enabled = !string.IsNullOrEmpty(textSend.Text);
        }
    }
}
4

3 回答 3

1 

if(string.IsNullOrEmpty(textIP.Text) || string.IsNullOrEmpty(textPort.Text) || string.IsNullOrEmpty(textName.Text))
{
   MessageBox.Show("请输入IP地址、端口号和名称");
}
别的
{
  //他们输入了东西...所以，尝试连接..
}

于 2010-01-15T03:34:21.380 回答
1

您可以使用TcpClient.Connected属性来检查连接是否已经建立。

如果（clientSocket.Connected）{
  ....在此处显示错误消息
}
别的{
  ... 前进  
}
于 2010-01-15T05:43:10.750 回答
0

您的表单包含对 aTcpClient和NetworkStream实例的引用。这两个都实现了IDisposable，因此它们必须被明确地处理掉。Dispose如果这些实例不为空，您必须覆盖表单的方法并处理这些实例。

于 2010-01-15T03:28:49.647 回答