QuickOPC User's Guide and Reference
WriteItem<TValue>(IEasyDAClient,String,String,String,TValue,DateTime,DAQuality) Method



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.DataAccess.Extensions Namespace > IEasyDAClientExtension2 Class > WriteItem Method : WriteItem<TValue>(IEasyDAClient,String,String,String,TValue,DateTime,DAQuality) Method
The type of item value.
The client object that will perform the operation.
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.
Contains ProgID of the OPC server to write into.
Contains OPC item identifier.
The typed value to be written.
The timestamp to be written.
The quality to be written.
Writes into a typed named item in an OPC server. A typed value, quality and timestamp are written. Writes a separately given typed value, timestamp and quality into a named item using individual parameters specifying its location.
Syntax
'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Sub WriteItem(Of TValue)( _
   ByVal client As IEasyDAClient, _
   ByVal machineName As String, _
   ByVal serverClass As String, _
   ByVal itemId As String, _
   ByVal value As TValue, _
   ByVal timestamp As Date, _
   ByVal quality As DAQuality _
) 
'Usage
 
Dim client As IEasyDAClient
Dim machineName As String
Dim serverClass As String
Dim itemId As String
Dim value As TValue
Dim timestamp As Date
Dim quality As DAQuality
 
IEasyDAClientExtension2.WriteItem(Of TValue)(client, machineName, serverClass, itemId, value, timestamp, quality)

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 to write into.
itemId
Contains OPC item identifier.
value
The typed value to be written.
timestamp
The timestamp to be written.
quality
The quality to be written.

Type Parameters

TValue
The type of item value.
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.

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.

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.

Remarks

The server can be local or can be remotely accessed via DCOM. Optionally, an access path can be specified or a specific data type can be requested.

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