使用ＯＰＣＮｅｔＡＰＩ连接OPCServer

 OPCServer KepServer;
        OPCGroup KepGroup;
        bool opc_connected;
        string remoteServerName = "KEPware.OPCSampleServer";
        string remoteServerIP = "";

        public OPCManagerService()
        {
            try
            {
                KepServer = new OPCServer();
                KepServer.Connect(remoteServerName, remoteServerIP);

                if (KepServer.ServerState != (int)OPCServerState.OPCRunning)
                {

                    //这里你可以根据返回的状态来自定义显示信息，请查看自动化接口API文档
                    //tsslServerState.Text = "状态：" + KepServer.ServerState.ToString() + "   ";
                    return;
                }
            }
            catch (Exception)
            {
                return;
            }

            opc_connected = true;

            KepServer.OPCGroups.DefaultGroupIsActive = true;
            KepServer.OPCGroups.DefaultGroupDeadband = 0f;  //the percentage change required before a change is reported, used to filter noise
            KepServer.OPCGroups.DefaultGroupUpdateRate = ;  //the rate is ms before item is updated

            KepGroup = KepServer.OPCGroups.Add("OPCDOTNETGROUP");
            KepGroup.IsSubscribed = false;
            KepGroup.OPCItems.DefaultIsActive = false;
        }

获取单个OPCItem的方法：

//OPCDataItemValue是自定义的一个类，用来保存OPCItem的实时数据
public OPCDataItemValue GetDataItemValue(string ItemID)
        {
            if (!opc_connected) return null;

            try
            {
                OPCItem item = KepGroup.OPCItems.AddItem(ItemID, );

                Object value;
                Object quality;
                Object timestamp;
                item.Read((short)OPCDataSource.OPCDevice, out value, out quality, out timestamp);

                OPCDataItemValue itemValue = new OPCDataItemValue();
                itemValue.DataValue = value;
                itemValue.TimeStamp = (DateTime)timestamp;
                itemValue.Quality = Convert.ToInt32(quality);

                Array removeServerHandle = (Array)(new int[] { , item.ServerHandle });
                Array removeErrors;
                KepGroup.OPCItems.Remove(, ref removeServerHandle, out removeErrors);

                return itemValue;
            }
            catch (Exception)
            {
               return null;
            }
        }

获取多个OPCItem的方法：

public List<OPCDataItemValue> GetDataItems(string ItemID)
        {
            if (!opc_connected) return null;

            try
            {
                List<OPCDataItemValue> dataItems = new List<OPCDataItemValue>();
                OPCDataItemValue opcDataItem = null;
                int[] itmHandleServer = new int[]; //index starts at 1
                OPCItem KepItem = KepGroup.OPCItems.AddItem(ItemID, );
                itmHandleServer[] = KepItem.ServerHandle;
                Array handles = (Array)itmHandleServer;

                Array values;
                Array errors;
                object qualities;
                object timestamps; //store the timestamp of the read

                //read directly from device
                KepGroup.SyncRead((short)OPCDataSource.OPCDevice, , ref handles, out values, out errors, out qualities, out timestamps);

                opcDataItem = new OPCDataItemValue();
                opcDataItem.ID = KepItem.ItemID;
                opcDataItem.DataValue = values.GetValue();
                Array t = (Array)timestamps;
                opcDataItem.TimeStamp = (DateTime)t.GetValue();
                Array q = (Array)qualities;
                opcDataItem.Quality = Convert.ToInt32(q.GetValue());

                dataItems.Add(opcDataItem);

                //删除OPCItem的方法和上面代码中的一样，这里就不写了。

                return dataItems;
            }
            catch (Exception)
            {
                return null;
            }
        }        

获取某ＯＰＣＩＴｅｍ的特定属性：

public OPCDataItemProperties GetDataItemProperties(string ItemID, List<int> PropertyIDs)
        {
            if (!opc_connected) return null;

            try
            {
                OPCDataItemProperties property = new OPCDataItemProperties();
                OPCItem item = KepGroup.OPCItems.AddItem(ItemID, );

                List<int> idList = new List<int>(PropertyIDs);
                idList.Insert(, );
                Array ids = (Array)idList.ToArray();

                int count = PropertyIDs.Count;
                Array values;
                Array errors;
                KepServer.GetItemProperties(ItemID, count, ref ids, out values, out errors);

                property.Count = count;
                property.IDs = ids;
                property.Values = values;
                property.Errors = errors;

                Array removeServerHandle = (Array)(new int[] { , item.ServerHandle });
                Array removeErrors;
                KepGroup.OPCItems.Remove(, ref removeServerHandle, out removeErrors);

                return property;
            }
            catch (Exception)
            {
                return null;
            }
        }

获取某OPCItem包含的所有属性：

 public OPCDataItemAvailableProperties GetDataItemAvailableProperties(string ItemID)
        {
            if (!opc_connected) return null;

            try
            {
                OPCDataItemAvailableProperties properties = new OPCDataItemAvailableProperties();
                OPCItem item = KepGroup.OPCItems.AddItem(ItemID, );

                int propertyCount;
                Array propertyIDs;
                Array propertyDescriptions;
                Array propertyDataTypes;
                KepServer.QueryAvailableProperties(ItemID, out propertyCount, out propertyIDs, out propertyDescriptions, out propertyDataTypes);

                properties.Count = propertyCount;
                properties.IDs = propertyIDs;
                properties.Descriptions = propertyDescriptions;
                properties.DataTypes = propertyDataTypes;

                Array removeServerHandle = (Array)(new int[] { , item.ServerHandle });
                Array removeErrors;
                KepGroup.OPCItems.Remove(, ref removeServerHandle, out removeErrors);

                return properties;
            }
            catch (Exception)
            {
                return null;
            }
        }