QuickOPC User's Guide and Reference
ReadItemValueArrayOfString(IEasyDAClient,ServerDescriptor,DANodeDescriptor,DAReadParameters) Method



OpcLabs.EasyOpcClassic Assembly > OpcLabs.EasyOpc.DataAccess.Extensions Namespace > IEasyDAClientExtension2 Class > ReadItemValueArrayOfString Method : ReadItemValueArrayOfString(IEasyDAClient,ServerDescriptor,DANodeDescriptor,DAReadParameters) Method
The client object that will perform the operation.
The OPC server involved in the operation.
The descriptor of the OPC node involved in the operation.
The read parameters (such as data source or value age).
Reads a value of named OPC item, and converts it to an array of System.String. The value is requested from the OPC server using a corresponding data type.
Syntax
'Declaration
 

<ExtensionAttribute()>
<ElementsCanBeNullAttribute()>
<NotNullAttribute()>
Public Overloads Shared Function ReadItemValueArrayOfString( _
   ByVal client As IEasyDAClient, _
   ByVal serverDescriptor As ServerDescriptor, _
   ByVal nodeDescriptor As DANodeDescriptor, _
   ByVal readParameters As DAReadParameters _
) As String()
'Usage
 

Dim client As IEasyDAClient
Dim serverDescriptor As ServerDescriptor
Dim nodeDescriptor As DANodeDescriptor
Dim readParameters As DAReadParameters
Dim value() As String
 
value = IEasyDAClientExtension2.ReadItemValueArrayOfString(client, serverDescriptor, nodeDescriptor, readParameters)
[Extension()]
[ElementsCanBeNull()]
[NotNull()]
public static string[] ReadItemValueArrayOfString( 
   IEasyDAClient client,
   ServerDescriptor serverDescriptor,
   DANodeDescriptor nodeDescriptor,
   DAReadParameters readParameters
)
[Extension()]
[ElementsCanBeNull()]
[NotNull()]
public:
static array<String^>^ ReadItemValueArrayOfString( 
   IEasyDAClient^ client,
   ServerDescriptor^ serverDescriptor,
   DANodeDescriptor^ nodeDescriptor,
   DAReadParameters^ readParameters
)

Parameters

client
The client object that will perform the operation.
serverDescriptor
The OPC server involved in the operation.
nodeDescriptor
The descriptor of the OPC node involved in the operation.
readParameters
The read parameters (such as data source or value age).

Return Value

Returns a value of the OPC item, converted to a type indicated by the method name.
Exceptions
ExceptionDescription
OpcLabs.EasyOpc.OperationModel.OpcExceptionThe OPC "Classic" (or OPC XML-DA) operation has failed.
System.ArgumentNullExceptionA null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.
Remarks
Using implicit conversions, you can pass an item ID in place of node descriptor. You can also pass a value age in place of read parameters
Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2012, Windows Server 2016; .NET Core, .NET 5, .NET 6: Linux, macOS, Microsoft Windows

See Also

Reference

IEasyDAClientExtension2 Class
IEasyDAClientExtension2 Members
Overload List

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