ChangeBrowsePosition Method

http://advosol.com/manuals/opcdanet/topic891.html

Change the current browse position. Move up, down or to in the hierarchical address space. ( IOPCBrowseServerAddressSpace:: ChangeBrowsePosition )
The function will return E_FAIL if called for a FLAT space. An error is returned if the passed string does not represent a 'branch'. Moving UP from the 'root' will return E_FAIL.
Note OPC_BROWSE_TO is new for version 2.0. Clients should be prepared to handle E_INVALIDARG if they pass this to a 1.0 server.

Syntax

Visual Basic (Usage)
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Dim instance As OpcServer
Dim direction As OPCBROWSEDIRECTION
Dim name As String
Dim value As Integer   value = instance.ChangeBrowsePosition(direction, name)

C#

public int ChangeBrowsePosition(    OPCBROWSEDIRECTION direction,    string name
)

Parameters

direction

IN: direction, up, down or to

name

IN: branch name to move to

Return Value

HRESULTS
Description

S_OK
Successful Read.

E_FAIL
The call failed with an unspecific error.

E_OUTOFMEMORY
Not enough memory.

OPC_E_INVALIDARG
An argument of the call was invalid.

Example

C#
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Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_UP, "" );  // to parent
Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_DOWN, "Device1" );
Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_TO, "" ); // to root
Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_TO, "Plant3.Section5.Device2" );

Visual Basic
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Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_UP, "" )  ' to parent
Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_DOWN, "Device1" )
Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_TO, "" )  ' to root
Srv.ChangeBrowsePosition( OPCBROWSEDIRECTION.OPC_BROWSE_TO, "Plant3.Section5.Device2" )

Requirements

OPC DA Server Version: V2

See Also

Reference

OpcServer Class
OpcServer Members