OPC Studio User's Guide and Reference
PullMultipleItemChanges Method (EasyDAClientCore)



OpcLabs.EasyOpcClassic Assembly > OpcLabs.EasyOpc.DataAccess Namespace > EasyDAClientCore Class : PullMultipleItemChanges Method
Maximum number of event notifications returned.

Valid values of this parameter are in the range from 1 to 2147483647 (Int32.MaxValue).

The number of milliseconds to wait, or System.Threading.Timeout.Infinite (-1) to wait indefinitely.
Attempts to pull multiple OPC item changes subscribed to by the IEasyDAClient.SubscribeMultipleItems or SubscribeItem method.
Syntax
'Declaration
 
Public Function PullMultipleItemChanges( _
   ByVal maximumCount As Integer, _
   ByVal millisecondsTimeout As Integer _
) As EasyDAItemChangedEventArgs()
'Usage
 
Dim instance As EasyDAClientCore
Dim maximumCount As Integer
Dim millisecondsTimeout As Integer
Dim value() As EasyDAItemChangedEventArgs
 
value = instance.PullMultipleItemChanges(maximumCount, millisecondsTimeout)

Parameters

maximumCount
Maximum number of event notifications returned.

Valid values of this parameter are in the range from 1 to 2147483647 (Int32.MaxValue).

millisecondsTimeout
The number of milliseconds to wait, or System.Threading.Timeout.Infinite (-1) to wait indefinitely.

Return Value

An array of event arguments, or null if no event is available within the specified time.

This method can return null (Nothing in Visual Basic).

The individual elements of the returned value are never null (Nothing in Visual Basic).

Exceptions
ExceptionDescription

One of the arguments provided to a method is not valid.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

The value of an argument is outside the allowable range of values as defined by the invoked method.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also