/// <summary>
/// 设置默认的OPC项，假如已添加，则移除后再重新添加（同一时刻默认标签只有一个）
/// </summary>
/// <param name="itemId">标签ID</param>
/// <param name="clientHandle">标签的客户端句柄</param>
/// <param name="message">返回的错误信息</param>
/// <returns></returns>
public bool SetItem(string itemId, int clientHandle, out string message)
{
try
{
if (this.DefaultGroupInfo == null)
{
message = "未找到默认组";
return(false);
}
//初始化OPC项信息并在默认OPC组中添加
List <OpcItemInfo> list = new List <OpcItemInfo>()
{
new OpcItemInfo(itemId, clientHandle)
};
this.DefaultGroupInfo.SetItems(list, out message);
if (this.DefaultGroupInfo.ItemCount > 0)
{
OpcItemInfo item = this.DefaultGroupInfo.ListItemInfo.Last();
//保存默认OPC项的客户端句柄，服务端句柄，标签名称
this.ItemHandleClient = item.ClientHandle;
this.ItemId = item.ItemId;
this.ItemHandleServer = item.ServerHandle;
}
}
catch (Exception ex)
{
this.ItemHandleClient = 0;
message = "移除或添加标签时发生错误:" + ex.Message;
return(false);
}
return(true);
}
/// <summary>
/// 根据给定的OPC项集合信息添加OPC项
/// </summary>
/// <param name="items">给出添加OPC项时所需信息的集合</param>
/// <param name="message">返回信息</param>
/// <returns></returns>
public bool SetItems(IEnumerable <OpcItemInfo> items, out string message)
{
message = string.Empty;
if (items == null || items.Count() == 0)
{
return(false);
}
try
{
//假如已存在OPC项，先移除
if (this.ItemCount > 0)
{
this.OpcGroup.OPCItems.Remove(this.ItemCount, ref this.server_handles, out this.errors);
}
List <OpcItemInfo> itemList = items.ToList(); //转换为新List对象，防止枚举改变对象时出现未知影响
this.ListItemInfo.Clear();
this.ListItemInfo.Add(this.opc_pack_basic);
itemList.Insert(0, this.opc_pack_basic);
this.item_ids = itemList.Select(p => p.ItemId).ToArray();
this.client_handles = itemList.Select(p => p.ClientHandle).ToArray();
this.OpcGroup.OPCItems.AddItems(itemList.Count - 1, ref this.item_ids, ref this.client_handles, out this.server_handles, out this.errors);
//添加OPC项后根据ID找到OPC项信息对象并设置服务端句柄，向OPC项信息List中添加
if (this.item_ids.Length > 1)
{
for (int i = 1; i < this.item_ids.Length; i++)
{
OpcItemInfo itemInfo = itemList.Find(p => p.ItemId.Equals(this.item_ids.GetValue(i)));
itemInfo.ServerHandle = int.Parse(this.server_handles.GetValue(i).ToString());
this.ListItemInfo.Add(itemInfo);
}
}
//假如添加后的数量对不上，则至少有一个OPC项未添加成功
if (this.ListItemInfo.Count < itemList.Count)
{
message = "至少有1个OPC项未添加成功";
}
}
catch (Exception ex)
{
message = string.Format("OPC组{0}移除或添加标签时发生错误:{1}", this.OpcGroup.Name, ex.Message);
return(false);
}
return(this.ListItemInfo.Count > 1); //假如至少有1个添加成功，返回true
}
/// <summary>
/// 为OPC组OPC项List内给定数量的、与给定服务端句柄对应的OPC项读取数据
/// </summary>
/// <param name="serverHandles">服务端句柄Array</param>
/// <param name="itemCount">读取的OPC项数量</param>
/// <param name="message">返回信息</param>
/// <returns></returns>
public bool ReadValues(Array serverHandles, /*int itemCount, */ out string message)
{
message = string.Empty;
object qualities, timeStamps;
Array values;
try
{
IEnumerable <int> temp = serverHandles == null || serverHandles.Length == 0 ? null : serverHandles.Cast <int>();
Array handles = this.GetServerHandles(temp);
int itemCount = handles.Length - 1;
this.OpcGroup.SyncRead((short)OPCDataSource.OPCDevice, itemCount, ref handles, out values, out this.errors, out qualities, out timeStamps);
//假如至少读取到1个值，根据服务端句柄找到OPC项信息并更新值
if (values.Length > 0)
{
for (int i = 1; i <= values.Length; i++)
{
OpcItemInfo itemInfo = this.ListItemInfo.Find(item => item.ServerHandle.Equals(handles.GetValue(i)));
if (itemInfo != null)
{
itemInfo.Value = values.GetValue(i).ToString();
}
}
}
if (values.Length < itemCount)
{
message = "至少有1个OPC项的值未找到";
}
GC.Collect();
}
catch (Exception ex)
{
message = string.Format("从名称为{0}的OPC组读取值失败：{1}", this.OpcGroup.Name, ex.Message);
return(false);
}
return(values.Length > 0);
}
