VB6 C# VB Code Converter

Table of Contents

• Downloads
• Background
• Before Conversion
• SharpDevelop
  • About SharpDevelop
  • About NRefactory
  • About AST and Parsing
  • SharpDevelop IDE and C# VB converters
  • C# and VB Language Equivalents and Comparison
  • Using SharpDevelop as a code converter
  • SharpDevelop Points of Interest
  • How to covert C# code
  • Demo conversion
  • Conversion Cases
• VB6 Upgrade Companion
  • VB 6 upgrading advantages
  • VB 6.0 upgrading disadvantages
  • Before Using VBUC
  • VBUC Trial version limitation
  • Other VB6 Converters
• Other Converters

Downloads

• Download CS2VB.cs.zip
• Download CS2VB.vb.zip
• SharpDevelop IDE External Link

Background

This article is about converting code to VB.Net.
It will discus SharpDevelop IDE and VB6 Upgrade Companion.

SharpDevelop IDE and NRefactory cover many conversion between deferent languages (C#, VB.Net, boo, Python, Ruby) and most other C# VB converter use the library NRefactory.

 VB6 Upgrade Companion witch will convert VB6 codes to C# or VB.Net. This software is selected because it is the only Microsoft partner to upgrade VB6

Before Conversion

• Make sure your code can be recompiled and run well before start converting.
• For C# and VB.Net 100% code conversion maybe get in many causes but not always. In some cases many post conversion fixing is required. 
• No convertors can grantee the 100% conversion.
• For other language pairs: Make sure the the target language support your project type.
• Please note the VB6 converting is a hard work because of the programing language philosophy is defer. please see VB6 section later is this article

SharpDevelop

Lots of C# <> VB code converter are available all most all of them are using Refactory library form SharpDevelop IDE to make the conversion and them make some useful post conversion fixing.

The power of NRefactory is parsing the code before the conversion; even if a keyword could take more than one meaning it could be converted correctly because of understanding the code line before the conversion. an other thing will make the converting possible is that both languages are extremely similar.

About SharpDevelop

• It's an freeware Open Source Development Environment for .NET.
• It could be used to make many useful code conversion.
• SharpDevelop IDE is the mother of NRefactory library which is the most uses converting library
• The conversion that done using SharpDevelop IDE is much beater.
• It provide a wide range of code conversion C#, VB.NET, Boo, Python, Ruby 

About NRefactory:

• ICSharpCode.NRefactory is freely available as a part of SharpDevelop IDE.
• It is parser library for C# and VB.
• It consists of a single Abstract Syntax Tree (AST) that can represent all constructs that are available in C# or VB (unlike System.CodeDom, which only represents constructs common to C# and VB).
• By using the C# parser and a VB output visitor (or vice versa), you can do a code converter.
• After parsing to AST, you can analyze and/or transform the AST and re-create source code from the (modified) AST, then re-insert the comments we saved from the parser into the output
• For more info about NRefactory please see: sharpdevelop.net and NRefactory wiki.
• You may try samples\NRefactoryDemo in the SharpDevelop source code to take a look how the AST parse source code.

About AST and Parsing:

The following example show a simple parsing proses.

SharpDevelop IDE and C# VB converters:

C# and VB Language Equivalents and Comparison

1. Language Equivalents
2. Comparison of C# and VB

Using SharpDevelop as a code converter:

1. Run SharpDevelop IDE
2. From file menu select open - project/solution and open the project to be converted
3. From View menu select projects
4. In the project window select the project to be converted
5. from project menu choose convert and then choose the target language
6. This will convert the whole project
7. The conversion could be done by right clicking the project icon in the project window then choose convert

SharpDevelop Points of Interest

How to covert C# code:

The code is converted using ICSharpCode.NRefactory.ParserFactory class:

Converter code in VB:

Imports ICSharpCode.NRefactory
Imports ICSharpCode.NRefactory.PrettyPrinter
Imports System.IO

Public Class CS2VB

    Public Overrides Function ConvertCode(ByVal sourceCode As String) As String        
            
            Dim specials As IList(Of ISpecial)
            Dim result As Ast.CompilationUnit
            Dim Parse_errors = ""
            Using parser As IParser = ParserFactory.CreateParser( _
                 SupportedLanguage.CSharp, New StringReader(sourceCode))
                parser.Parse()
                'this allows retrieving comments, preprocessor directives, etc. 
                '(stuff that isn't part of the syntax)
                specials = parser.Lexer.SpecialTracker.RetrieveSpecials()
                'this retrieves the root node of the result AS
                result = parser.CompilationUnit
                If parser.Errors.Count > 0 Then
                    Parse_errors = parser.Errors.ErrorOutput
                End If
            End Using

            'Now you can analyze and/or transform the AST.
            'Should you want to re-create source code from the (modified) AST, 
            'use an output visitor: 
            're-insert the comments we saved from the parser into the output
            
            Dim outputVisitor As New PrettyPrinter.VBNetOutputVisitor
            Dim astViewUnit = result
            Using SpecialNodesInserter.Install(specials, outputVisitor)
                astViewUnit.AcceptVisitor(outputVisitor, Nothing)
            End Using
            Dim outputCode = outputVisitor.Text
            'By using the C# parser and a VB output visitor (or vice versa), 
            'you can build a code converter. Of course, 
            'the real Code Converter in SharpDevelop also transforms the AST to fix cases 
            'where C# and VB semantics differ.

            Return outputCode   

    End Function
End Class/pre>

Converter code in C#:

using ICSharpCode.NRefactory;
using ICSharpCode.NRefactory.PrettyPrinter;
using System.IO;

public class CS2VB
{

    public override string ConvertCode(string sourceCode)
    {
        //var names and format is as in http://wiki.sharpdevelop.net/NRefactory.ashx

        //ICSharpCode.NRefactory is a parser library for C# and VB.
        //It consists of a single Abstract Syntax Tree (AST) 
        //that can represent all constructs that are available in C# or VB 
        //(unlike System.CodeDom, which only represents constructs common to C# 
        //and VB).
        //Please try samples\NRefactoryDemo in the SharpDevelop source code 
        //to take a look at the AST
        //To parse source code, use: 
        IList specials;
        Ast.CompilationUnit result;
        object Parse_errors = "";
        using (IParser parser = ParserFactory.CreateParser(SupportedLanguage.CSharp, new 
                StringReader(sourceCode))) {
            parser.Parse();
            // this allows retrieving comments, preprocessor directives, etc. 
            //(stuff that isn't part of the syntax)
            specials = parser.Lexer.SpecialTracker.RetrieveSpecials();
            // this retrieves the root node of the result AST
            result = parser.CompilationUnit;
            if (parser.Errors.Count > 0) {
                MessageBox.Show(parser.Errors.ErrorOutput, "Parse errors");
            }
        }
        //Now you can analyze and/or transform the AST.
        //Should you want to re-create source code from the (modified) AST, 
        //use an output visitor: 
        //re-insert the comments we saved from the parser into the output
        PrettyPrinter.VBNetOutputVisitor outputVisitor = new 
                PrettyPrinter.VBNetOutputVisitor();
        object astViewUnit = result;
        using (SpecialNodesInserter.Install(specials, outputVisitor)) {
            astViewUnit.AcceptVisitor(outputVisitor, null);
        }
        object outputCode = outputVisitor.Text;
        //By using the C# parser and a VB output visitor (or vice versa), 
        //you can build a code converter. Of course, 
        //the real Code Converter in SharpDevelop also transforms the AST 
        //to fix cases 
        //where C# and VB semantics differ.

        return outputCode;

    }
}

Demo conversion:

Partial code convert is not supported code should be in class and in method.

Demo1:

class Class1{void sub1(){
    //your code start
    int x =0;
    //your code end
}}

The result in VB

Class Class1
    Sub sub1()
        'your code start
        Dim x As Integer = 0
        'your code end
    End Sub
End Class

Demo 2:

namespace WindowsFormsApplication1{
    partial class Form1
    {
        private System.ComponentModel.IContainer components = null;
		private System.Windows.Forms.TextBox textbox1;
        private System.Windows.Forms.TextBox textbox2;

        
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        private void InitializeComponent()
        {
            this.textbox1 = new System.Windows.Forms.TextBox();
            this.textbox2 = new System.Windows.Forms.TextBox();
            this.SuspendLayout();
            // 
            // textbox1
            // 
            this.textbox1.Location = new System.Drawing.Point(30, 30);
            this.textbox1.Name = "TEXTBOX1";
            this.textbox1.Size = new System.Drawing.Size(80, 20);
            this.textbox1.TabIndex = 0;
            // 
            // textbox2
            // 
            this.textbox2.Location = new System.Drawing.Point(30, 60);
            this.textbox2.Name = "textbox";
            this.textbox2.Size = new System.Drawing.Size(80, 20);
            this.textbox2.TabIndex = 1;
            this.textbox2.TextChanged += new System.EventHandler(this.textbox_TextChanged);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(284, 262);
            this.Controls.Add(this.textbox2);
            this.Controls.Add(this.textbox1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.ResumeLayout(false);
            this.PerformLayout();

        }
        
        public Form1()
        {
            InitializeComponent();
        }

        private void textbox_TextChanged(object sender, EventArgs e)
        {
            string x = "";
            string X = "";
        }
    }
}

The result in VB

Namespace WindowsFormsApplication1
	Partial Class Form1
		Private components As System.ComponentModel.IContainer = Nothing
		Private textbox1 As System.Windows.Forms.TextBox
		Private textbox2 As System.Windows.Forms.TextBox


		Protected Overrides Sub Dispose(disposing As Boolean)
			If disposing AndAlso (components IsNot Nothing) Then
				components.Dispose()
			End If
			MyBase.Dispose(disposing)
		End Sub

		Private Sub InitializeComponent()
			Me.textbox1 = New System.Windows.Forms.TextBox()
			Me.textbox2 = New System.Windows.Forms.TextBox()
			Me.SuspendLayout()
			' 
			' textbox1
			' 
			Me.textbox1.Location = New System.Drawing.Point(30, 30)
			Me.textbox1.Name = "TEXTBOX1"
			Me.textbox1.Size = New System.Drawing.Size(80, 20)
			Me.textbox1.TabIndex = 0
			' 
			' textbox2
			' 
			Me.textbox2.Location = New System.Drawing.Point(30, 60)
			Me.textbox2.Name = "textbox"
			Me.textbox2.Size = New System.Drawing.Size(80, 20)
			Me.textbox2.TabIndex = 1
			AddHandler Me.textbox2.TextChanged, New System.EventHandler(AddressOf Me.textbox_TextChanged)
			' 
			' Form1
			' 
			Me.AutoScaleDimensions = New System.Drawing.SizeF(6F, 13F)
			Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
			Me.ClientSize = New System.Drawing.Size(284, 262)
			Me.Controls.Add(Me.textbox2)
			Me.Controls.Add(Me.textbox1)
			Me.Name = "Form1"
			Me.Text = "Form1"
			Me.ResumeLayout(False)
			Me.PerformLayout()

		End Sub

		Public Sub New()
			InitializeComponent()
		End Sub

		Private Sub textbox_TextChanged(sender As Object, e As EventArgs)
			Dim x__1 As String = ""
			Dim X__2 As String = ""
		End Sub
	End Class
End Namespace

Conversion Cases:

Case sensitive C# to VB:

The converter will automatically rename object if needed.

Event Handler C# to VB:

The event C# handler will be converted as follows:

C#:

this.textbox2.TextChanged += new System.EventHandler(this.textbox_TextChanged);

VB:

AddHandler Me.textbox2.TextChanged, New System.EventHandler(AddressOf Me.textbox_TextChanged)

VB6 Upgrade Companion VBUC:

If you are not familiar with upgrading VB6 then you will not under stand how useful the software. It same too much of the upgrade time also it is in most time required many post conversion works.
It is much better than the old upgrade engine that is included in versions 2003, 2005 and 2008 of VS

VB 6.0 upgrading advantages

• Supporting 64 bit
• Faster running
• More resources
• Improve the maintenance of an application
• Increase developer productivity

VB 6.0 upgrading disadvantages

• Compile on demand will be lost.
• The resulting application need dot net farmworker will the original one is not
• If your application is a dynamic library; note that pre declared object is not supported in C# or vb.Net.
• If your application is ActiveX control or ActiveX Document then there is no acceptable converter for you; manual code rewriting is needed.
• The converter we save your time for converting but post conversion work is much needed.

What VBUC can upgrade:

• Modules, Classes, Forms & MDIForms
• User Controls that used in the same project on in the same group
• Resource File

What VBUC can't upgrade:

• Property Page
• Designer files (*.Dsr)
• User Controls that used in web browser or ActiveX container
• ActiveX Document

Before Using VBUC:

The VBUC is feather software with many option and we should study before start converting:

• It is better to install VB6 but it is not a must
• Ensure that your application could be recompiled and run correctly.
• Ensure that all your referred library are available and work well in the current operating system.
• It is more simple to convert to VB.Net than C#.
• For ActiveX choose Com Visible
• Form options Use helper classes whenever it available
• For making you application more like .net designed use More dot net option 
• If the above option fail use the More Automation options for less error in conversion.
• After converting complete open your project in VS and disable all warning and switch option explicit off and option strict off.
• If error is still appears try to fix them manually.
• Once you are able to compile your project try to follow warning
• Switch option explicit on and option strict on and follow any errors appears

VBUC Trial version limitation:

It is work for project with less than 10000 line code

Other VB6 Converters:

• DeluxVBNET
• vb2c
• VB6 to C#
• vb2delphi

Other Converters:

VB6 to .NET

• VB6 Upgrade Companion

ASP to .NET

• Converting ASP to ASP.NET
• ASP to ASP.NET 1.x Migration Assistant

Java to .NET

• Java Language Conversion Assistant 2.0
• Janett - Java to .Net Translator
• CSharpJavaMerger Framework
• Java 2 CSharp Translator for Eclipse

PHP to .NET

• Migrating from PHP to ASP.NET
• PHP to ASP.NET 1.x Migration Assistant

C++ to .NET

• C++ to C# Translator
• code2code

ColdFusion to .NET

• Migrating from ColdFusion to ASP.NET
• Migrating AnandTech from Macromedia ColdFusion to ASP.NET

History

• Initial version.