[C#.NET][TCP Socket] 利用 Socket 控制 Advantech RU25 Reader-Passive Mode
日前，因為在控制這台 Reader 設備的時候短缺原廠的 command set / get 文件，於是利用原廠提供的 Demo software + Smart Sniff 來觀察 TCP Package，我也會用 Smart Sniff 來驗証資料傳遞之間是否有問題。
除了 Smart Sniff 之外，我也力推免費軟體 Wireshark，功能較為強大，相信大家都有聽過它，相當的實用，市面上也有相關的書籍，實戰封包分析－使用 Wireshark (Practical Packet Analysis: Using Wireshark to Solve Real-World Network Problems, 2/e)
工具準備好之後，就可以來開始處理它了。
Step1.Conect：
跟前面幾篇一樣建立一個新的 Socket Class，並且 調用Socket.Connect 方法。
var ipAddress = IPAddress.Parse(this.Config.IpAddress);
var iPEndPoint = new IPEndPoint(ipAddress, this.Config.Port);
//Create a TCP/IP socket.
this._socketCliect = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
EndPoint endPoint = (EndPoint)iPEndPoint;
this._socketCliect.Connect(endPoint);
當連線成功的時候，Reader 不會拋訊息回來，不用寫 Receive，也就是不需要帳號/密碼，在網路的世界裡，欠缺安全性這方面的考量。
完整的 Connect 方法如下，因為設備的特性所以我必須要送出一些參數命令，比如連續兩次的 set readmode 0，才能在某些情況下取得正確的 Receive data(這是實驗得知的特性)
private Socket _socketCliect = null; private Encoding _encode = Encoding.ASCII; public bool Connect() { if (this.Config == null) { return false; } if (this.IsConnected) { return true; } var ipAddress = IPAddress.Parse(this.Config.IpAddress); var iPEndPoint = new IPEndPoint(ipAddress, this.Config.Port); //Create a TCP/IP socket. this._socketCliect = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); EndPoint endPoint = (EndPoint)iPEndPoint; this._socketCliect.Connect(endPoint); if (this._socketCliect.Connected) { SendAndReceive("set readmode 0"); var readmode = SendAndReceive("set readmode 0"); var inventorymode = this.SendAndReceive("set inventorymode 0"); if (readmode == MESSAGE_SUCCESS && inventorymode == MESSAGE_SUCCESS) { this.IsConnected = true; } else { this.IsConnected = false; } } return this.IsConnected; }
Setp2.Send Command Set：
跟設備搭上線後便可以對它送出 ASCII 命令，當我調用 Socket.Send 方法 送出資料 後，就要調用 Socket.Receive 方法去 拿回資料，然後驗證拿到的資料是否正確。
下圖為原廠提供設備回傳的資料格式：
根據文件，程式碼如下，在這裡我只檢查最後6個 byte[] { 49, 49, 48, 50, 13, 10 }，也就是 1102\r\n ，若在時間內收到最後這 6 個 byte 則離開迴圈並回傳資料，若在時間內拿不到這最後的 byte[] ，表示網路接收逾時(ReceiveTimeout)，則離開迴圈。
public static readonly string MESSAGE_SUCCESS = "1101\r\n701\r\n1102\r\n"; public string SendAndReceive(string Data)
{
if (this.Config == null)
{
return null;
}
if (this._socketCliect == null || !this._socketCliect.Connected)
{
return null;
}
SocketError error = new SocketError();
var command = string.Concat(Data, "\r");
var sentCommand = this.Encode.GetBytes(command);
this._socketCliect.Send(sentCommand, 0, sentCommand.Length, SocketFlags.None, out error);
var tempTimeOut = this._socketCliect.ReceiveTimeout;
this._socketCliect.ReceiveTimeout = 1000;
var bufferArray = new byte[256];
var socketError = new SocketError();
MemoryStream memory = new MemoryStream();
byte[] expect = new byte[] { 49, 49, 48, 50, 13, 10 };
byte[] target = new byte[6];
while (true)
{
var receiveCount = this._socketCliect.Receive(bufferArray, 0, bufferArray.Length, SocketFlags.None, out socketError);
if (receiveCount == 0 || socketError != SocketError.Success)
{
break;
}
memory.Write(bufferArray, 0, receiveCount);
if (memory.Length < expect.Length)
{
continue;
}
var startIndex = memory.Length - expect.Length;
memory.Seek(startIndex, SeekOrigin.Begin);
memory.Read(target, 0, expect.Length);
var compare = expect.SequenceEqual(target);
if (compare)
{
break;
}
}
this._socketCliect.ReceiveTimeout = tempTimeOut;
byte[] response = memory.ToArray();
var result = this.Encode.GetString(response, 0, response.Length);
if (memory != null)
{
memory.Close();
}
return result;
}
下圖為 set 命令的封包傳送結果
Setp3.Send Command Get：
設備除了有 set 之外，當然還會有 get。
下圖為 get command 所回傳的資料格式：
當我調用 SendAndReceive("get readmode") 方法，就能觀察到以下的資料
每一個功能的 get 回傳的資料格式以及 return code 都不太一樣，return code 是用來驗證資料格式是否正確的旗標，所以要 用力的 看文件，若沒文件就觀察 Smart Sniff。
依照文件規則 get command 產生了以下程式碼：
public string getValidData(string data, string returnCode)
{
if (string.IsNullOrEmpty(data) | string.IsNullOrEmpty(returnCode))
{
return null;
}
var split = data.Split(new string[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntri
if (split.Length <= 3)
{
return null;
}
var commandIndex = 0;
var endIndex = split.Length - 1;
var returnIndex = split.Length - 2;
var commandCode = split[commandIndex];
var endCode = split[endIndex];
if (commandCode != "1101" && endCode != "1102" && split[returnIndex] != returnCode)
{
return null;
}
StringBuilder builder = new StringBuilder();
for (int i = 0; i < split.Length; i++)
{
if (i == commandIndex | i == endIndex | i == returnIndex)
{
continue;
}
builder.Append(split[i]);
}
return builder.ToString();
}
inventory command，是我手頭上所擁有的稀有文件資料，正好也算是一個最重要的命令，就以它來當例子，當我調用 SendAndReceive("inventory")，會得到以下的結果，它所回傳的結果是多筆的
如下圖，inventory 所定義的資料格式
針對 inventory 的命令包裝成一個方法，然後調用 getValidData 方法，驗證是否為合法資料。
public IEnumerable<TagStatus> InventoryTag()
{
if (!this.IsConnected)
{
return null;
}
var response = this.SendAndReceive("inventory");
if (string.IsNullOrEmpty(response))
{
return null;
}
var data = getValidData(response, "101");
List<TagStatus> tagStatusList = new List<TagStatus>();
foreach (var d in data)
{
var tag = TagStatus.Parse(d);
tagStatusList.Add(tag);
}
return tagStatusList;
}
用來裝載資料的 TagStatus 類別
public class TagStatus : INotifyPropertyChanged
{
private string _tagEpc;
private string _memory;
private int _antennaNumber;
private double _rssiAver;
private double _rssiMax;
private double _rssiMin;
private string _pc;
public string TagEpc
{
get { return _tagEpc; }
set
{
_tagEpc = value;
OnPropertyChanged("TagEpc");
}
}
public int AntennaNumber
{
get { return _antennaNumber; }
set
{
_antennaNumber = value;
OnPropertyChanged("AntennaNumber");
}
}
public double RSSI_Aver
{
get { return _rssiAver; }
set
{
_rssiAver = value;
OnPropertyChanged("RSSI_Aver");
}
}
public double RSSI_Min
{
get { return _rssiMin; }
set
{
_rssiMin = value;
OnPropertyChanged("RSSI_Min");
}
}
public double RSSI_Max
{
get { return _rssiMax; }
set
{
_rssiMax = value;
OnPropertyChanged("RSSI_Max");
}
}
public string PC
{
get { return _pc; }
set
{
_pc = value;
OnPropertyChanged("PC");
}
}
public string Memory
{
get { return _memory; }
set
{
_memory = value;
OnPropertyChanged("Memory");
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string name)
{
PropertyChangedEventHandler changedEventHandler = this.PropertyChanged;
if (changedEventHandler == null)
return;
changedEventHandler((object)this, new PropertyChangedEventArgs(name));
}
public override string ToString()
{
return string.Format("TagEpc:{0}", this.TagEpc);
}
public static TagStatus Parse(string data)
{
// "3000E2003411B802011618152459,0002,4A,4A,4A";
// "3000E2003411B802011618152459,000000000,0002,4A,4A,4A";
if (string.IsNullOrEmpty(data))
{
return null;
}
var split = data.Split(',');
var index = split.Length;
if (index < 5)
{
return null;
}
TagStatus tagStatus = new TagStatus();
tagStatus.TagEpc = split[0].Substring(4);
tagStatus.PC = split[0].Substring(0, 4);
if (index == 5)
{
// "3000E2003411B802011618152459,0002,4A,4A,4A";
tagStatus.AntennaNumber = int.Parse(split[1]);
tagStatus.RSSI_Min = Convert.ToInt32(split[2], 16);
tagStatus.RSSI_Max = Convert.ToInt32(split[3], 16);
tagStatus.RSSI_Aver = Convert.ToInt32(split[4], 16);
}
else if (index == 6)
{
// "3000E2003411B802011618152459,000000000,0002,4A,4A,4A";
tagStatus.Memory = split[1];
tagStatus.AntennaNumber = int.Parse(split[2]);
tagStatus.RSSI_Min = Convert.ToInt32(split[3], 16);
tagStatus.RSSI_Max = Convert.ToInt32(split[4], 16);
tagStatus.RSSI_Aver = Convert.ToInt32(split[5], 16);
}
return tagStatus;
}
}
若有謬誤，煩請告知，新手發帖請多包涵
Microsoft MVP Award 2010~2017 C# 第四季
Microsoft MVP Award 2018~2022 .NET
