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copied!<p>I made a couple of changes to make your code work. </p> <ol> <li>The Variable constructor is changed to use the ActivityFunc overload </li> <li>The second WriteLine needs to call ToString() explicitly in the expression</li> </ol> <p>The corrected code is as follows </p> <pre><code>private static void Main(string[] args) { var testClass = new Test { MyString = "some string", MyBool = true }; var wf = new Sequence { Variables = { // Changed to use ActivityFunc so testClass is not interpreted as a literal new Variable<Test>("varName", ctx => testClass), }, Activities = { new WriteLine { Text = new VisualBasicValue<string>( "\"Test Class Properties: \" & varName.MyString & \"-\" & varName.MyBool") }, // Changed to call ToString explicitly new WriteLine { Text = new VisualBasicValue<string>("\"Test Class ToString(): \" & varName.ToString()") } } }; var settings = new VisualBasicSettings(); settings.ImportReferences.Add( new VisualBasicImportReference { Assembly = typeof(Test).Assembly.GetName().Name, Import = typeof(Test).Namespace }); // construct workflow VisualBasic.SetSettings(wf, settings); WorkflowInvoker.Invoke(wf); Console.ReadKey(); } </code></pre> <p>One more thing. Some have questioned why it was necessary to call Test.ToString() explicitly with the VB Concat operator. This is a curious issue and it is one of the places where a type declared in C# differs from a type declared in VB.</p> <p>C# uses the + operator for both addition and concatenation where VB has the & operator for concat and a specific IL instruction op_Concat.</p> <p>If you declare your type in VB, you can overload the & operator to eliminate the need to call ToString() in your expression.</p> <p>For example</p> <pre><code>Public Class Test Public Property MyString As String Public Property MyBool As Boolean Public Overrides Function ToString() As String Return "Test Class : " & MyString + " - " & MyBool End Function Public Shared Operator &(ByVal left As String, ByVal right As Test) As String Return left & "-" & right.ToString End Operator End Class </code></pre> <p>When working on problems like in VB I often just create VB console apps to test things out apart from Workflow</p> <pre><code>Module Module1 Dim varName As New Test With {.MyBool = True, .MyString = "some string"} Sub Main() Console.WriteLine("Test Class Properties: " & varName.MyString & "-" & varName.MyBool) Console.WriteLine("Test Class ToString(): " & varName) Console.ReadKey() End Sub End Module </code></pre> <p>The IL emitted for this app shows the operator </p> <pre><code>IL_002f: ldstr "Test Class ToString(): " IL_0034: ldsfld class VBTest.Test VBTest.Module1::varName IL_0039: call string VBTest.Test::op_Concatenate(string, class VBTest.Test) IL_003e: call void [mscorlib]System.Console::WriteLine(string) </code></pre>

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