QuerySourceConditions Method (IEasyAEClientExtension)

Finds out event conditions associated with the specified source name. Computer name and server class are used for specifying the OPC server.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
<ElementsNotNullAttribute()>
<NotNullAttribute()>
Public Shared Function QuerySourceConditions( _
   ByVal client As IEasyAEClient, _
   ByVal machineName As String, _
   ByVal serverClass As String, _
   ByVal sourceNodeDescriptor As AENodeDescriptor _
) As AEConditionElementCollection

'Usage
 
Dim client As IEasyAEClient
Dim machineName As String
Dim serverClass As String
Dim sourceNodeDescriptor As AENodeDescriptor
Dim value As AEConditionElementCollection
 
value = IEasyAEClientExtension.QuerySourceConditions(client, machineName, serverClass, sourceNodeDescriptor)

[Extension()]
[ElementsNotNull()]
[NotNull()]
public static AEConditionElementCollection QuerySourceConditions( 
   IEasyAEClient client,
   string machineName,
   string serverClass,
   AENodeDescriptor sourceNodeDescriptor
)

[Extension()]
[ElementsNotNull()]
[NotNull()]
public:
static AEConditionElementCollection^ QuerySourceConditions( 
   IEasyAEClient^ client,
   String^ machineName,
   String^ serverClass,
   AENodeDescriptor^ sourceNodeDescriptor
)

Parameters

client: The client object that will perform the operation.
machineName: Name of the machine. Determines the computer on which the OPC server is located. May be an empty string, in which case the OPC server is assumed to exist on the local computer or at the computer specified for it by DCOM configuration.
serverClass: Contains ProgID of the OPC server.
sourceNodeDescriptor: A source node descriptor, usually expressed as qualified source name. Only the conditions associated with this source are returned.

Return Value

A collection of condition elements, one element for each condition of the given source.

Exceptions

Exception Description

Exception	Description
System.ArgumentException	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.
System.ArgumentNullException	A `null` reference (`Nothing` in Visual Basic) is passed to a method that does not accept it as a valid argument. 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.
OpcLabs.EasyOpc.OperationModel.OpcException	The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause. This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

System.ArgumentException

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.

System.ArgumentNullException

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

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.

OpcLabs.EasyOpc.OperationModel.OpcException

The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

Requirements

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

Reference

IEasyAEClientExtension Class
IEasyAEClientExtension Members

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