c#地秤接口（数据接收）

【核心代码】

using System;
using System.Collections.Generic;
using System.Text;

namespace LABin
{

    public class LABinSPort
    {
        private System.IO.Ports.SerialPort _SPort;

        public delegate void PortDataChangeEventHandler(object PortData);
        public event PortDataChangeEventHandler PortDataChangeEvent;


        /// <summary>
        /// 初始化端口
        /// </summary>
        /// <param name="portName">端口名字</param>
        /// <param name="baudRate">波特率</param>
        public LABinSPort(string portName, int baudRate)
        {
            _SPort = new System.IO.Ports.SerialPort(portName, baudRate);
            _SPort.DataReceived  = SPort_DataReceived;
        }

        /// <summary>
        /// 打开端口
        /// </summary>
        /// <returns></returns>
        public Boolean Open()
        {
            try
            {
                if (!_SPort.IsOpen)
                {
                    _SPort.Open();
                }
                return _SPort.IsOpen;
            }
            catch (Exception)
            {
                _SPort.Close();
                return false;
            }

        }

        /// <summary>
        /// 关闭端口
        /// </summary>
        /// <returns></returns>
        public Boolean Close()
        {
            if (_SPort.IsOpen)
            {
                _SPort.Close();
            }
            return !_SPort.IsOpen;
        }

        /// <summary>
        /// 端口
        /// </summary>
        public System.IO.Ports.SerialPort SPort
        {
            get
            {
                return _SPort;
            }
        }

        /// <summary>
        /// 数据接收事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void SPort_DataReceived(System.Object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
        {
            try
            {
                if (_SPort.BytesToRead > 0)
                {
                    Int32 n = _SPort.BytesToRead;

                    if (n < 100) { return; }

                    byte[] buf = new byte[n];

                    _SPort.Read(buf, 0, n);

                    string[] str = Encoding.ASCII.GetString(buf).Split(new char[] { '\r', '\n' });

                    foreach (string s in str)
                    {
                        //检查输出是否符合格式wn0000.105kg
                        if (s.StartsWith("wn") && s.EndsWith("kg"))
                        {
                            decimal w;
                            if (decimal.TryParse(s.Substring(2, 8), out w))
                            {
                                //引发事件
                                if (PortDataChangeEvent != null)
                                {
                                    PortDataChangeEvent(w);
                                }
                            }
                        }
                    }
                }
            }
            catch (Exception)
            {
                _SPort.Close();
            }
        }
    }
}