INGEAR.NET - ASP.NET Web Service Code (C#)

You can use this source as a starting point to develop your own ASP.NET Web services or Web-based HMI for PLC's using INGEAR.NET

The web service consists of 2 classes

The Service1 class that exposes our WebMethods

using System; using System.Collections.Generic; using System.Web; using System.Web.Services; using PLCCommClass; namespace WebService { /// <summary> /// Summary description for Service1 /// </summary> [WebService(Namespace = "http://plcdotnet.com/")] [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] [System.ComponentModel.ToolboxItem(false)] public class Service1 : System.Web.Services.WebService { /// <summary> /// PLCService is singleton pattern class that continually /// reads data from the PLC /// </summary> PLCService netplc = PLCService.Instance; /// <summary> /// returns a PLC Value or an error /// </summary> /// <param name="Name"> /// PLC Data Table /// N7:0 - N7:4 /// F8:0 - F8:4 /// B3:0/0 - B3:0/4 /// </param> /// <returns> /// /// </returns> [WebMethod] public string getTagValue(String Name) { return netplc.TagGetValue(Name); } /// <summary> /// Sets a PLC Value /// </summary> /// <param name="Name"></param> /// PLC Data Table /// N7:0 - N7:4 /// F8:0 - F8:4 /// B3:0/0 - B3:0/4 /// <param name="Value"> /// data value to write to PLC /// </param> /// <returns> /// </returns> [WebMethod] public string setTagValue(String Name, String Value) { return netplc.TagSetValue(Name, Value); } /// <summary> /// getTagTimeStamp /// </summary> /// <param name="Name"></param> /// <returns></returns> [WebMethod] public String getTagTimeStamp(String Name) { return netplc.TagGetTimeStamp(Name); } /// <summary> /// getTagQualCode /// </summary> /// <param name="Name"> /// Register Address /// </param> /// <returns></returns> [WebMethod] public int getTagQualCode(String Name) { return netplc.TagGetQualCode(Name); } /// <summary> /// Returns the Tag.Quality /// </summary> /// <param name="Name"></param> /// <returns></returns> [WebMethod] public string getTagQualString(String Name) { return netplc.TagGetQualString(Name); } /// <summary> /// Returns the Controller.ErrorCode /// </summary> /// <returns></returns> [WebMethod] public int getControllerErrorCode() { return netplc.ControllerGetErrorCode(); } /// <summary> /// Returns the Controller.ErrorString /// </summary> /// <returns></returns> [WebMethod] public string getControllerErrorString() { return netplc.ControllerGetErrorString(); } } }

The PLCService class implements a Singleton Pattern .  A Singleton pattern is used to limit the number of
connections to the PLC to only one regardless of the number concurrent page views. This saves on PLC communication
and network resources.

using System; using System.Collections.Generic; using System.Text; using ABLink; using System.Threading; namespace PLCCommClass { /// <summary> /// This is a Singleton pattern clas /// the singleton pattern is a design pattern that is used /// to restrict instantiation of a class to one object. /// </summary> public sealed class PLCService { static PLCService instance = null; static readonly object padlock = new object(); /// <summary> /// Instance of the ABLINK.Controller class for READING rfom the PLC /// </summary> Controller readPLC = new Controller(); /// <summary> /// Instance of the ABLINK.Controller class for WRITING to the PLC /// </summary> Controller writePLC = new Controller(); /// <summary> /// Instance of the ABLINK.TagGroup for optimized communication /// </summary> TagGroup group = new TagGroup(); /// <summary> /// Instance of the Thread class for background updates /// </summary> Thread updateThread = null; PLCService() { Initialize(); } ~PLCService() { if (null != updateThread) { updateThread.Abort(); group.Clear(); readPLC.Disconnect(); writePLC.Disconnect(); } } public static PLCService Instance { get { lock (padlock) { if (instance == null) { instance = new PLCService(); } return instance; } } } /// <summary> /// Initializes connection and populates group with some tag classes /// </summary> internal void Initialize() { try { // connect to the PLC if (false == readPLC.IsConnected) { readPLC.IPAddress = PLC_IP_ADDRESS; readPLC.Path = "0"; readPLC.DriverType = Controller.Driver.ENET; readPLC.CPUType = Controller.CPU.PLC; readPLC.Timeout = 8000; readPLC.Connect(); writePLC.IPAddress = readPLC.IPAddress; writePLC.Path = readPLC.Path; writePLC.DriverType = readPLC.DriverType; writePLC.CPUType = readPLC.CPUType; writePLC.Timeout = readPLC.Timeout; writePLC.Connect(); } // create and add tags to the group. group.AddTag(new Tag("N7:0")); group.AddTag(new Tag("N7:1")); group.AddTag(new Tag("N7:2")); group.AddTag(new Tag("N7:3")); group.AddTag(new Tag("N7:4")); group.AddTag(new Tag("F8:0")); group.AddTag(new Tag("F8:1")); group.AddTag(new Tag("F8:2")); group.AddTag(new Tag("F8:3")); group.AddTag(new Tag("F8:4")); group.AddTag(new Tag("B3:0/0")); group.AddTag(new Tag("B3:0/1")); group.AddTag(new Tag("B3:0/2")); group.AddTag(new Tag("B3:0/3")); group.AddTag(new Tag("B3:0/4")); // start the background thread for updates if (updateThread == null) { updateThread = new Thread(plcUpdate); updateThread.Start(); } } catch (SystemException ex) { throw new SystemException(ex.Message, ex.InnerException); } } private void plcUpdate() { while (instance != null) { if (group.Count > 0) readPLC.GroupRead(group); Thread.Sleep(1000); } } /// <summary> /// returns error code with readPLC /// </summary> /// <returns></returns> internal int ControllerGetErrorCode() { return readPLC.ErrorCode; } /// <summary> /// returns error string with readPLC /// </summary> /// <returns></returns> internal String ControllerGetErrorString() { return readPLC.ErrorString; } /// <summary> /// returns Tag.QualityCode if Tag.Name exists in group /// </summary> /// <param name="tagName"> /// Tag.Name (e.g. "N7:0","F8:0", "B3:0/0") /// </param> /// <returns> /// </returns> internal int TagGetQualCode(String tagName) { Tag theTag = null; String findTag = ""; tagName = tagName.ToUpper(); tagName = tagName.Replace(";", ":"); for (int i = 0; i < group.Count; i++) { theTag = (Tag)group.Tags[i]; findTag = theTag.Name.ToUpper(); if (tagName.Equals(findTag)) break; } if (null == theTag) return ABLink.ResultCode.E_FAIL; return theTag.QualityCode; } /// <summary> /// Returns Tag.QualityString /// </summary> /// <param name="tagName"> /// Tag.Name (e.g. "N7:0","F8:0", "B3:0/0") /// /// </param> /// <returns></returns> internal String TagGetQualString(String tagName) { Tag theTag = null; String findTag = ""; tagName = tagName.ToUpper(); tagName = tagName.Replace(";", ":"); for (int i = 0; i < group.Count; i++) { theTag = (Tag)group.Tags[i]; findTag = theTag.Name.ToUpper(); if (tagName.Equals(findTag)) break; } if (null == theTag) return ABLink.ResultCode.ES_FAIL; return theTag.QualityString; } /// <summary> /// Returns Tag.TimeStamp /// </summary> /// <param name="tagName"> /// Tag.Name (e.g. "N7:0","F8:0", "B3:0/0") /// </param> /// <returns></returns> internal String TagGetTimeStamp(String tagName) { Tag theTag = null; String findTag = ""; tagName = tagName.ToUpper(); tagName = tagName.Replace(";", ":"); for (int i = 0; i < group.Count; i++) { theTag = (Tag)group.Tags[i]; findTag = theTag.Name.ToUpper(); if (tagName.Equals(findTag)) break; } if (null == theTag) return ABLink.ResultCode.ES_FAIL; return theTag.TimeStamp.ToString(); } /// <summary> /// Returns Tag.Value /// </summary> /// <param name="tagName"> /// Tag.Name (e.g. "N7:0","F8:0", "B3:0/0") /// </param> /// <returns></returns> internal string TagGetValue(String tagName) { Tag theTag = null; String findTag = ""; tagName = tagName.ToUpper(); tagName = tagName.Replace(";", ":"); for (int i = 0; i < group.Count; i++) { theTag = (Tag)group.Tags[i]; findTag = theTag.Name.ToUpper(); if (tagName.Equals(findTag)) break; } if (null == theTag) return ABLink.ResultCode.ES_FAIL; if (theTag.Value != null) return Convert.ToString(theTag.Value); return theTag.ErrorString; } /// <summary> /// Writes a value to the PLC /// </summary> /// <param name="tagName"> /// Tag.Name (e.g. "N7:0","F8:0", "B3:0/0") /// </param> /// <param name="Value"> /// Value to write (e.g. "1234", "123.678", "True/False") /// </param> /// <returns></returns> internal string TagSetValue(String tagName, String Value) { Tag theTag = null; String findTag = ""; tagName = tagName.ToUpper(); tagName = tagName.Replace(";", ":"); for (int i = 0; i < group.Count; i++) { theTag = (Tag)group.Tags[i]; findTag = theTag.Name.ToUpper(); if (tagName.Equals(findTag)) break; } if (null == theTag) return ABLink.ResultCode.ES_FAIL; theTag.Value = Value; writePLC.WriteTag(theTag); if (theTag.ErrorCode == ABLink.ResultCode.E_SUCCESS) { if (theTag.QualityCode == ABLink.ResultCode.QUAL_GOOD) return Value; } return theTag.ErrorString; } } }