WriteValueAction<TValue>(UADataVariable,TypeCode,Action<TValue>) Method

Makes data variable that consumes the attribute data using the write value action. Specify the declared type code.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
<NotNullAttribute()>
Public Overloads Shared Function WriteValueAction(Of TValue)( _
   ByVal dataVariable As UADataVariable, _
   ByVal declaredTypeCode As TypeCode, _
   ByVal writeValueAction As Action(Of TValue) _
) As UADataVariable

'Usage
 
Dim dataVariable As UADataVariable
Dim declaredTypeCode As TypeCode
Dim writeValueAction As Action(Of TValue)
Dim value As UADataVariable
 
value = UADataVariableExtension.WriteValueAction(Of TValue)(dataVariable, declaredTypeCode, writeValueAction)

[Extension()]
[NotNull()]
public static UADataVariable WriteValueAction<TValue>( 
   UADataVariable dataVariable,
   TypeCode declaredTypeCode,
   Action<TValue> writeValueAction
)

[Extension()]
[NotNull()]
public:
static UADataVariable^ WriteValueActiongeneric<typename TValue>
( 
   UADataVariable^ dataVariable,
   TypeCode declaredTypeCode,
   Action<TValue^>^ writeValueAction
)

Parameters

dataVariable: The data variable that will be modified and returned.
The value of this parameter cannot be null (Nothing in Visual Basic).
declaredTypeCode: The declared type of the data variable, expressed as .NET type code (System.TypeCode).
writeValueAction: The write value action, i.e. the action that accepts the value to be written and performs the write operation.
The value of this parameter cannot be null (Nothing in Visual Basic).

Type Parameters

TValue

Return Value

Returns the , internally modified as defined by the method.

This method never returns null (Nothing in Visual Basic).

Exceptions

Exception Description

Exception	Description
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.
System.ArgumentOutOfRangeException	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.
System.ComponentModel.InvalidEnumArgumentException	An invalid enumeration value was used. 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.

System.ArgumentOutOfRangeException

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.

System.ComponentModel.InvalidEnumArgumentException

An invalid enumeration value was used.

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.

Remarks

This method overload infers the OPC data type and value rank (always OpcLabs.EasyOpc.UA.UAValueRanks.Scalar) of the data variable from the declaredTypeCode parameter. The type used in your code to implement the data variable behavior can be different, and it will be TValue. OPC Wizard provides automatic value conversions. This can be useful in case your language makes it more difficult to process some .NET types, as is the case e.g. with VB.NET and unsigned integer types such as System.UInt32. In this case, for example, if you want a data variable of OPC type UInt32, you can set declaredTypeCode to System.TypeCode.UInt32, but use a System.Int64 as the type of your action argument (TValue).

This is an extension method (info: C#, VB.NET). In languages that have support for extensions methods (such as C# and VB.NET), you can use the extension method as if it were a regular method on the object that is its first parameter. In other languages (such as with Python.NET), you will call the extension as a static method, and pass it the object on which it acts as its first parameter.

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

UADataVariableExtension Class
UADataVariableExtension Members
Overload List

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