C#与MySQL读写中文字符避免乱码指南

try
{
    IPAddress MyIP = IPAddress.Parse("127.0.0.1");
    TcpListener MyListener = new TcpListener(MyIP, Convert.ToInt16("1235"));
    MyListener.Start();
    Socket MySocket = MyListener.AcceptSocket();
    
    // 1. 接收并解码：使用 UTF8.GetString 防止中文乱码
    byte[] MyData = new byte[256];
    MySocket.Receive(MyData);
    // 假设 MyData 中包含有效字节，去除末尾空字节后解码
    string receivedText = System.Text.Encoding.UTF8.GetString(MyData.TakeWhile(b => b != 0).ToArray());
    this.richTextBox1.AppendText(receivedText);

    // 2. 发送并编码：将中文转为 UTF8 字节流
    string sendMessage = "From Server:你好!我是服务器";
    byte[] sendBytes = System.Text.Encoding.UTF8.GetBytes(sendMessage);
    MySocket.Send(sendBytes);
}
catch (Exception ex)
{
    MessageBox.Show(ex.Message, "信息提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
}

try
{
    TcpClient MyClient = new TcpClient();
    MyClient.Connect("127.0.0.1", Convert.ToInt16("1235"));
    Stream MyStream = MyClient.GetStream();
    
    // 1. 发送并编码：将含中文的字符串转为 UTF8 字节数组
    string sendText = "From Client:你好!我是客户端";
    byte[] MySendByte = System.Text.Encoding.UTF8.GetBytes(sendText);
    MyStream.Write(MySendByte, 0, MySendByte.Length);
    
    // 2. 接收并解码：读取响应字节并还原为中文
    byte[] MyData = new byte[256];
    int bytesRead = MyStream.Read(MyData, 0, 256);
    string responseText = System.Text.Encoding.UTF8.GetString(MyData, 0, bytesRead);
    this.richTextBox1.AppendText(responseText);
}
catch(Exception ex)
{
    MessageBox.Show(ex.Message, "信息提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
}

// 假设连接字符串已配置为默认支持utf8mb4
string m_ConnectionStrings = "server=localhost;uid=xx;pwd=xx;database=db;Allow User Variables=True;";
using (SqlConnection MyConnect = new SqlConnection(m_ConnectionStrings))
{
    // 推荐使用 Parameterized Query
    string MySQL = "INSERT INTO [BSM_SystemServiceInfoTable] VALUES (@AgentID, @Col1, @Col2, @Col3, @Col0)";
    using (SqlCommand MyCommand = new SqlCommand(MySQL, MyConnect))
    {
        // 添加参数，ADO.NET 会根据 SqlDbType.NChar/NVarChar 自动处理 Unicode 编码
        MyCommand.Parameters.AddWithValue("@AgentID", AgentID);
        MyCommand.Parameters.AddWithValue("@Col1", data[1]);
        MyCommand.Parameters.AddWithValue("@Col2", data[2]);
        MyCommand.Parameters.AddWithValue("@Col3", data[3]);
        MyCommand.Parameters.AddWithValue("@Col0", data[0]);
        
        MyCommand.Connection.Open();
        MyCommand.ExecuteNonQuery();
        MyCommand.Connection.Close();
    }
}