'Declaration
<ExtensionAttribute()> Public Overloads Shared Function SubscribeItem( _ ByVal client As IEasyDAClient, _ ByVal machineName As String, _ ByVal serverClass As String, _ ByVal itemId As String, _ ByVal requestedUpdateRate As Integer, _ ByVal state As Object _ ) As Integer
'Usage
Dim client As IEasyDAClient Dim machineName As String Dim serverClass As String Dim itemId As String Dim requestedUpdateRate As Integer Dim state As Object Dim value As Integer value = IEasyDAClientExtension.SubscribeItem(client, machineName, serverClass, itemId, requestedUpdateRate, state)
[Extension()] public static int SubscribeItem( IEasyDAClient client, string machineName, string serverClass, string itemId, int requestedUpdateRate, object state )
[Extension()] public: static int SubscribeItem( IEasyDAClient^ client, String^ machineName, String^ serverClass, String^ itemId, int requestedUpdateRate, Object^ state )
Parameters
- client
- The client object that will perform the operation.
This is typically the EasyDAClient object.
The value of this parameter cannot be
null
(Nothing
in Visual Basic). - machineName
- Name of the machine (empty string for local computer).
The value represents a UNC or DNS computer name. Any string can be passed to this parameter (i.e. will not cause System.ArgumentException), but not all values make sense and will work when an operation using them is attempted. IPv6 addresses are normally enclosed between '[' and ']'.
The value of this parameter cannot be
null
(Nothing
in Visual Basic). - serverClass
- Contains ProgID of the OPC server.
The value of this parameter cannot be
null
(Nothing
in Visual Basic). - itemId
- ID of the item that will be subscribed to.
The value of this parameter cannot be
null
(Nothing
in Visual Basic). - requestedUpdateRate
- How often should the updates be received (number of milliseconds)
- state
- The state object (can be any object supplied by your code); available in event notifications.
The value of this parameter can be
null
(Nothing
in Visual Basic).