Visual Basic (Usage)	Copy Code
Dim instance As OpcXmlDA Dim asyncResult As IAsyncResult Dim RItemList As SubscribeReplyItemList Dim Errors As OPCError() Dim ServerSubHandle As String Dim value As ReplyBase   value = instance.EndSubscribe(asyncResult, RItemList, Errors, ServerSubHandle)

public ReplyBase EndSubscribe( 
   IAsyncResult asyncResult,
   out SubscribeReplyItemList RItemList,
   out OPCError[] Errors,
   out string ServerSubHandle
)

Parameters

asyncResult

The reference to the pending asynchronous request to wait for.

RItemList

The RItemList structure is the container for Item elements which carry error or value information. The readily available item values are sent back via Item elements in RItemList if and only if the client requested them with “ReturnValuesOnReply” (see Subscribe). If the server does not have a value for some of the items at the time of Subscribe, the response will provide no value element for the affected item.
If error conditions (like invalid item name or unsupported rate) are detected by the server, then Item Elements will be returned to communicate the error conditions.
If ReturnValuesOnReply is “false” and no errors are found, RItemList will be empty.

Errors

An array of OPCError elements with the description of the errors occured in this server call. Errors are only present if Items contain result codes.

ServerSubHandle

Supplied by the Server. It must be used for SubscriptionPolledRefresh and SubscriptionCancel. ServerSubHandle is specific to the client making the request.

Return Value

Target Platforms:Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows 7, Windows Server 2008 family

Reference