This simplified Read overload does not return a cancel ID and therefore does not allow the call to be cancelled.
Overload List
| Overload | Description |
|---|---|
| Read(String,Int32) | Read the current value of one item. An asynchronous OpcGroup read call is executed. The value is returned in the ReadComplete callback handler. This simplified Read overload does not return a cancel ID and therefore does not allow the call to be cancelled. |
| Read(String,Int32,Int32) | Read the current value of one item. An asynchronous OpcGroup read call is executed. The value is returned in the ReadComplete callback handler. The returned cancel ID can be used to cancel the call execution. |
| Read(ItemDef,Int32) | Read the current value of the item specified by the ItemDef object. An asynchronous OpcGroup read call is executed. The value is returned in the ReadComplete callback handler. This simplified Read overload does not return a cancel ID and therefore does not allow the call to be cancelled. |
| Read(ItemDef,Int32,Int32) | Read the current value of the item specified by the ItemDef object. An asynchronous OpcGroup read call is executed. The value is returned in the ReadComplete callback handler. The returned cancel ID can be used to cancel the call execution. |
| Read(OPCDATASOURCE,String,OPCItemState) | Read the current value of the specified item. The item is added to the group if it is not yet added. A synchronous OpcGroup read function is executed. (Inherited from OPCDA.NET.SyncIOGroup) |
| Read(OPCDATASOURCE,ItemDef,OPCItemState) | Read the current value of the item specified with the ItemDef object. The ItemDef object was created in a previous Read or Add call. This method overload is a bit more efficient because no ItemID search as to be done. Only in a SyncIOGroup with many items could be a significant performance gain. A synchronous OpcGroup read function is executed. (Inherited from OPCDA.NET.SyncIOGroup) |