' Build a Hello World program graph using 
' System.CodeDom types.
Public Shared Function BuildHelloWorldGraph() As CodeCompileUnit

    ' Create a new CodeCompileUnit to contain 
    ' the program graph.
    Dim compileUnit As New CodeCompileUnit()

    ' Declare a new namespace called Samples.
    Dim samples As New CodeNamespace("Samples")

    ' Add the new namespace to the compile unit.
    compileUnit.Namespaces.Add(samples)

    ' Add the new namespace import for the System namespace.
    samples.Imports.Add(New CodeNamespaceImport("System"))

    ' Declare a new type called Class1.
    Dim class1 As New CodeTypeDeclaration("Class1")

    ' Add the new type to the namespace type collection.
    samples.Types.Add(class1)

    ' Declare a new code entry point method.
    Dim start As New CodeEntryPointMethod()

    ' Create a type reference for the System.Console class.
    Dim csSystemConsoleType As New CodeTypeReferenceExpression( _
        "System.Console")

    ' Build a Console.WriteLine statement.
    Dim cs1 As New CodeMethodInvokeExpression( _
        csSystemConsoleType, "WriteLine", _
        New CodePrimitiveExpression("Hello World!"))

    ' Add the WriteLine call to the statement collection.
    start.Statements.Add(cs1)

    ' Build another Console.WriteLine statement.
    Dim cs2 As New CodeMethodInvokeExpression( _
        csSystemConsoleType, "WriteLine", _
        New CodePrimitiveExpression("Press the Enter key to continue."))

    ' Add the WriteLine call to the statement collection.
    start.Statements.Add(cs2)

    ' Build a call to System.Console.ReadLine.
    Dim csReadLine As New CodeMethodInvokeExpression( _
        csSystemConsoleType, "ReadLine")

    ' Add the ReadLine statement.
    start.Statements.Add(csReadLine)

    ' Add the code entry point method to
    ' the Members collection of the type.
    class1.Members.Add(start)

    Return compileUnit
End Function