添加主）事件处理程序（的SerialPort [英] Adding event handler in main() for SerialPort

问题描述

我尝试订阅一个事件处理程序接收到的事件的数据。好像我不能指定事件处理函数的名称。我不明白为什么结果
myComPort.DataReceived + =新SerialDataReceivedEventHandler（comPort_DataReceived）;是给我的错误信息。
这是问题所在，希望任何人都可以回答这个问题。

 命名空间的SerialPort 
 {
公共类节目
 { 
 
内部列表<&字节GT; portBuffer =新的List<&字节GT;（1024）; 
 
静态无效的主要（）
 {
 
 
 // 1。找到可用的COM端口
的String [] nameArray = NULL; 
字符串myComPortName = NULL; 
 nameArray = SerialPort.GetPortNames（）; 
如果（nameArray.GetUpperBound（0）> = 0）
 {
 myComPortName = nameArray [0]; 
} 
，否则
 {
 Console.WriteLine（错误）; 
的回报; 
} 
 
 
 // 2。创建一个对象的serialport 
 //端口对象是通过使用使用自动关闭（）
的SerialPort myComPort =新的SerialPort（）; 
 myComPort.DataReceived + =新SerialDataReceivedEventHandler（comPort_DataReceived）; 
 myComPort.PortName = myComPortName; 
 //默认paramit为9600，无奇偶校验，一个停止位，无流控制
 
 
 
 //3.open港口
尝试
 {
 myComPort.Open（）; 
} 
赶上（UnauthorizedAccessException前）
 {
 MessageBox.Show（ex.Message）; 
} 
 //添加超时，P161 
 
 //读取字节
字节[] = ByteBuffer中新的字节[10]; 
的Int32计数; 
的Int32 numberOfReceivedBytes; 
 myComPort.Read（ByteBuffer的，0，9）; 
为（计数= 0; COUNT< = 3;计数++）
 {
 Console.WriteLine（ByteBuffer的[统计]的ToString（））; 
} 
 
 
} 
 //事件处理程序应该是静态的？ 
无效comPort_DataReceived（对象发件人，SerialDataReceivedEventArgs E）
 {
 INT numberOfBytesToRead; 
 numberOfBytesToRead = myComPort.BytesToRead; 
字节[] = newReceivedData新的字节[numberOfBytesToRead] 
 myComPort.Read（newReceivedData，0，numberOfBytesToRead）; 
 portBuffer.AddRange（newReceivedData）; 
过程数据（）; 
} 
私人无效过程数据（）
 {
 //当8个字节已经抵达，然后显示屏和缓冲区
 INT删除它们计数; 
 INT numberOfBytesToRead = 8; 
 
如果（portBuffer.Count> = numberOfBytesToRead）
 {
为（计数= 0; COUNT< numberOfBytesToRead;计数++）
 {
控制台.WriteLine（（炭）（portBuffer [计数]））; 
} 
 portBuffer.RemoveRange（0，numberOfBytesToRead）; 
} 
} 
 
} 
 
} 
  

解决方案

在事件处理程序，myComPort是不在范围内 - 它在你的main（）方法本地声明。我建议你抽取COM端口处理到一个类，使myComPort该类的成员变量。

另外，您的意见指出，SerialPort类具有管理资源，它需要配置使用了IDisposable /使用模式，但你没有使用块包裹访问通讯端口。

最后，该方法您要添加的事件处理程序中存在的一个实例成员，而不是作为一个静态成员;从main（）方法的静态范围内访问它，你需要从这个类的一个实例，抓住它，或使该方法是静态的。

I try to subscribe a event handler to the data received event. Seems like I cant specify the event handler function name. I dont understand why
myComPort.DataReceived += new SerialDataReceivedEventHandler(comPort_DataReceived); is giving me error message. Here is the problem, hope anyone can answer it.

namespace serialport
{
    public class Program
    {

        internal List<Byte> portBuffer = new List<Byte>(1024);

        static void Main()
        {


            //1. find available COM port
            string[] nameArray = null;
            string myComPortName = null;
            nameArray = SerialPort.GetPortNames();
            if (nameArray.GetUpperBound(0) >= 0)
            {
                myComPortName = nameArray[0];
            }
            else
            {
                Console.WriteLine("Error");
                return;
            }


            //2. create a serialport object
            // the port object is closed automatically by use using()
            SerialPort myComPort = new SerialPort();
            myComPort.DataReceived += new SerialDataReceivedEventHandler(comPort_DataReceived);
            myComPort.PortName = myComPortName;
            //the default paramit are 9600,no parity,one stop bit, and no flow control



            //3.open the port
            try
            {
                myComPort.Open();
            }
            catch (UnauthorizedAccessException ex)
            {
                MessageBox.Show(ex.Message);
            }
            //Add timeout, p161

            //reading Bytes
            byte[] byteBuffer = new byte[10];
            Int32 count;
            Int32 numberOfReceivedBytes;
            myComPort.Read(byteBuffer, 0, 9);
            for (count = 0; count <= 3; count++)
            {
                Console.WriteLine(byteBuffer[count].ToString());
            }


        }
        //The event handler should be static??
        void comPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            int numberOfBytesToRead;
            numberOfBytesToRead = myComPort.BytesToRead;
            byte[] newReceivedData = new byte[numberOfBytesToRead];
            myComPort.Read(newReceivedData, 0, numberOfBytesToRead);
            portBuffer.AddRange(newReceivedData);
            ProcessData();
        }
        private void ProcessData()
        {
            //when 8 bytes have arrived, display then and remove them from the buffer
            int count;
            int numberOfBytesToRead = 8;

            if (portBuffer.Count >= numberOfBytesToRead)
            {
                for (count = 0; count < numberOfBytesToRead; count++)
                {
                    Console.WriteLine((char)(portBuffer[count]));
                }
                portBuffer.RemoveRange(0, numberOfBytesToRead);
            }
        }

    }

    }

解决方案

In your event handler, myComPort isn't in scope - it's declared locally in your main() method. I would suggest that you extract the com port handling into a class and make myComPort a member variable of that class.

Also, your comments note that the SerialPort class has a managed resource that it needs to dispose of using the IDisposable / Using pattern, but you don't have a using block wrapping the access to the comm port.

Last, the method you are adding as the event handler exists as an instance member rather than as a static member; to access it from the main() method's static scope, you need to either grab it from an instance of the class or make the method static.

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