OPC Studio User's Guide and Reference
ResolveEncodingIdFromDataTypeId Method (_UADataTypeModelProvider)
Example 



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OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.DataTypeModel.ComTypes Namespace > _UADataTypeModelProvider Interface : ResolveEncodingIdFromDataTypeId Method
A data type ID.

The value of this parameter cannot be null (Nothing in Visual Basic).

The encoding name.

Because the OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName has an implicit conversion from System.String, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use a string (representing the expanded text of the qualified name) in place of this parameter, and the corresponding OPC UA qualified name will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the UAQualifiedName Constructor(String) constructor instead.

The value of this parameter cannot be null (Nothing in Visual Basic).

Resolves an encoding ID from a given data type ID and an encoding name.
Syntax
'Declaration
 
<NotNullAttribute()>
Function ResolveEncodingIdFromDataTypeId( _
   ByVal dataTypeId As Object, _
   ByVal encodingName As Object _
) As ValueResult
 
'Usage
 
Dim instance As _UADataTypeModelProvider
Dim dataTypeId As Object
Dim encodingName As Object
Dim value As ValueResult
 
value = instance.ResolveEncodingIdFromDataTypeId(dataTypeId, encodingName)

Parameters

dataTypeId
A data type ID.

The value of this parameter cannot be null (Nothing in Visual Basic).

encodingName
The encoding name.

Because the OpcLabs.EasyOpc.UA.AddressSpace.UAQualifiedName has an implicit conversion from System.String, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use a string (representing the expanded text of the qualified name) in place of this parameter, and the corresponding OPC UA qualified name will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the UAQualifiedName Constructor(String) constructor instead.

The value of this parameter cannot be null (Nothing in Visual Basic).

Return Value

A value result with the encoding ID obtained.

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

Remarks

The standard browse names to be used with encodingName are:

You can obtain the data type model provider interface (OpcLabs.EasyOpc.UA.DataTypeModel.IUADataTypeModelProvider) from the OpcLabs.EasyOpc.UA.Plugins.ComplexData.IEasyUAClientComplexData.DataTypeModelProvider property of the OpcLabs.EasyOpc.UA.Plugins.ComplexData.IEasyUAClientComplexData service.

This member or type is for use from COM. It is not meant to be used from .NET or Python. Refer to the corresponding .NET member or type instead, if you are developing in .NET or Python.

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.

Example
// Shows how to obtain data type description object for complex data node with OPC UA Complex Data plug-in, and the actual
// content of the data type dictionary.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

using System;
using System.Text;
using Microsoft.Extensions.DependencyInjection;
using OpcLabs.BaseLib.OperationModel.Generic;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace;
using OpcLabs.EasyOpc.UA.AddressSpace.Standard;
using OpcLabs.EasyOpc.UA.DataTypeModel;
using OpcLabs.EasyOpc.UA.DataTypeModel.Extensions;
using OpcLabs.EasyOpc.UA.InformationModel;
using OpcLabs.EasyOpc.UA.Plugins.ComplexData;

namespace UADocExamples.ComplexData._IUADataTypeDictionaryProvider
{
    class ResolveDataTypeDescriptorFromDataTypeEncodingId
    {
        public static void Main1()
        {
            // Define which server we will work with.
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

            // Instantiate the client object.
            var client = new EasyUAClient();

            // Obtain the data type ID.
            //
            // In many cases, you would be able to obtain the data type ID of a particular node by reading its DataType
            // attribute, or easier, by calling the extension method ReadDataType on the IEasyUAClient interface. The sample
            // server, however, shows a more advanced approach in which the data type ID refers to an abstract data type,
            // and the actual values are then sub-types of this base data type. This abstract data type does not have any
            // encodings associated with it and it is therefore not possible to extract its description from the server.
            // We therefore use a hard-coded data type ID for one of the sub-types in this example.
            //
            // The code to obtain the data type ID for given node would normally look like this:
            //    UANodeId dataTypeId = client.ReadDataType(
            //        endpointUriString,
            //        "nsu=http://test.org/UA/Data/ ;i=10239");    // [ObjectsFolder]/Data.Static.Scalar.StructureValue
            //
            UANodeId dataTypeId = "nsu=http://test.org/UA/Data/ ;i=9440";    // ScalarValueDataType

            // Get the IEasyUAClientComplexData service from the client. This is needed for advanced complex data 
            // operations.
            IEasyUAClientComplexData complexData = client.GetService<IEasyUAClientComplexData>();

            // Get the data type model provider. Provides methods to access data types in OPC UA model.
            IUADataTypeModelProvider dataTypeModelProvider = complexData.DataTypeModelProvider;

            // Resolve the data type ID from our data type ID, for encoding name "Default Binary".
            ValueResult<UAModelNodeDescriptor> encodingIdResult = dataTypeModelProvider.ResolveEncodingIdFromDataTypeId(
                new UAModelNodeDescriptor(endpointDescriptor, dataTypeId),
                UABrowseNames.DefaultBinary);
            // Check if the operation succeeded. Use the ThrowIfFailed method instead if you want exception be thrown.
            if (!encodingIdResult.Succeeded)
            {
                Console.WriteLine("*** Failure: {0}", encodingIdResult.ErrorMessageBrief);
                return;
            }
            UAModelNodeDescriptor encodingId = encodingIdResult.Value;

            // Get the data type dictionary provider. Provides methods to access data type dictionaries in OPC UA model.
            IUADataTypeDictionaryProvider dataTypeDictionaryProvider = complexData.DataTypeDictionaryProvider;

            // Resolve the data type descriptor from the encoding ID.
            ValueResult<UADataTypeDescriptor> dataTypeDescriptorResult =
                dataTypeDictionaryProvider.ResolveDataTypeDescriptorFromDataTypeEncodingId(encodingId);
            // Check if the operation succeeded. Use the ThrowIfFailed method instead if you want exception be thrown.
            if (!dataTypeDescriptorResult.Succeeded)
            {
                Console.WriteLine("*** Failure: {0}", dataTypeDescriptorResult.ErrorMessageBrief);
                return;
            }
            UADataTypeDescriptor dataTypeDescriptor = dataTypeDescriptorResult.Value;

            // The data type descriptor contains two pieces of information:
            // The data type dictionary ID: This determines the dictionary where the data type is defined.
            Console.WriteLine(dataTypeDescriptor.DataTypeDictionaryId);
            // And the data type description: It is a "pointer" into the data type dictionary itself, selecting a specific 
            // type definition inside the data type dictionary. The format of it depends on the data type system;
            // in our case, it is a string that is the name of one of the type elements in the XML document of the data type
            // dictionary.
            Console.WriteLine(dataTypeDescriptor.DataTypeDescription);

            // Obtain the actual content of the data type dictionary.
            ValueResult<byte[]> dataTypeDictionaryResult =
                dataTypeDictionaryProvider.GetDataTypeDictionaryFromDataTypeDictionaryId(dataTypeDescriptor.DataTypeDictionaryId);
            // Check if the operation succeeded. Use the ThrowIfFailed method instead if you want exception be thrown.
            if (!dataTypeDictionaryResult.Succeeded)
            {
                Console.WriteLine("*** Failure: {0}", dataTypeDictionaryResult.ErrorMessageBrief);
                return;
            }
            byte[] dataTypeDictionary = dataTypeDictionaryResult.Value;

            // The data type dictionary returned is an array of bytes; its syntax and semantics depends on the data type 
            // system. In our case, we know that the data type dictionary is actually a string encoded in UTF-8.
            string text = Encoding.UTF8.GetString(dataTypeDictionary);
            Console.WriteLine();
            Console.WriteLine(text);


            // Example output (truncated):
            //
            //http://opcua.demo-this.com:51211/UA/SampleServer; NodeId="nsu=http://test.org/UA/Data/ ;ns=2;i=11422"
            //ScalarValueDataType
            //
            //<opc:TypeDictionary
            //  xmlns:opc="http://opcfoundation.org/BinarySchema/"
            //  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            //  xmlns:ua="http://opcfoundation.org/UA/"
            //  xmlns:tns="http://test.org/UA/Data/"
            //  DefaultByteOrder="LittleEndian"
            //  TargetNamespace="http://test.org/UA/Data/"
            //>
            //  <!-- This File was generated on 2013-01-22 and supports the specifications supported by version 1.1.334.0 of the OPC UA deliverables. -->
            //  <opc:Import Namespace="http://opcfoundation.org/UA/" Location="Opc.Ua.BinarySchema.bsd"/>
            //
            //  <opc:StructuredType Name="ScalarValueDataType" BaseType="ua:ExtensionObject">
            //    <opc:Field Name="BooleanValue" TypeName="opc:Boolean" />
            //    <opc:Field Name="SByteValue" TypeName="opc:SByte" />
            //    <opc:Field Name="ByteValue" TypeName="opc:Byte" />
            //    <opc:Field Name="Int16Value" TypeName="opc:Int16" />
            //    <opc:Field Name="UInt16Value" TypeName="opc:UInt16" />
            //    <opc:Field Name="Int32Value" TypeName="opc:Int32" />
            //    <opc:Field Name="UInt32Value" TypeName="opc:UInt32" />
            //    <opc:Field Name="Int64Value" TypeName="opc:Int64" />
            //    <opc:Field Name="UInt64Value" TypeName="opc:UInt64" />
            //    <opc:Field Name="FloatValue" TypeName="opc:Float" />
            //    <opc:Field Name="DoubleValue" TypeName="opc:Double" />
            //    <opc:Field Name="StringValue" TypeName="opc:String" />
            //    <opc:Field Name="DateTimeValue" TypeName="opc:DateTime" />
            //    <opc:Field Name="GuidValue" TypeName="opc:Guid" />
            //    <opc:Field Name="ByteStringValue" TypeName="opc:ByteString" />
            //    <opc:Field Name="XmlElementValue" TypeName="ua:XmlElement" />
            //    <opc:Field Name="NodeIdValue" TypeName="ua:NodeId" />
            //    <opc:Field Name="ExpandedNodeIdValue" TypeName="ua:ExpandedNodeId" />
            //    <opc:Field Name="QualifiedNameValue" TypeName="ua:QualifiedName" />
            //    <opc:Field Name="LocalizedTextValue" TypeName="ua:LocalizedText" />
            //    <opc:Field Name="StatusCodeValue" TypeName="ua:StatusCode" />
            //    <opc:Field Name="VariantValue" TypeName="ua:Variant" />
            //    <opc:Field Name="EnumerationValue" TypeName="ua:Int32" />
            //    <opc:Field Name="StructureValue" TypeName="ua:ExtensionObject" />
            //    <opc:Field Name="Number" TypeName="ua:Variant" />
            //    <opc:Field Name="Integer" TypeName="ua:Variant" />
            //    <opc:Field Name="UInteger" TypeName="ua:Variant" />
            //  </opc:StructuredType>
            //
            //  <opc:StructuredType Name="ArrayValueDataType" BaseType="ua:ExtensionObject">
            //    <opc:Field Name="NoOfBooleanValue" TypeName="opc:Int32" />
            //    <opc:Field Name="BooleanValue" TypeName="opc:Boolean" LengthField="NoOfBooleanValue" />
            //    <opc:Field Name="NoOfSByteValue" TypeName="opc:Int32" />
        }
    }
}
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