This last weekend I expirimented a little bit with extending the functionality of the RichTextBox control. Below you'll find an example of a small class that enherits from the RichTextBox control and allows you to implement syntax highlighting (with the use of a couple Win32 API call to smooth over the process of course.) The code pretty much speaks for itself.

Public Class SyntaxRTB

   Inherits System.Windows.Forms.RichTextBox

   Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" _
      (ByVal hWnd As IntPtr, ByVal wMsg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer

   Private Declare Function LockWindowUpdate Lib "user32" (ByVal hWnd As Integer) As Integer

   Private _SyntaxHighlight_CaseSensitive As Boolean = False

   Private Words As New DataTable

   'Contains Windows Messages for the SendMessage API call
   Private Enum EditMessages
      LineIndex = 187
      LineFromChar = 201
      GetFirstVisibleLine = 206
      CharFromPos = 215
      PosFromChar = 1062
   End Enum

   Protected Overrides Sub OnTextChanged(ByVal e As System.EventArgs)
      ColorVisibleLines()
   End Sub

   Public Sub ColorRtb()
      Dim FirstVisibleChar As Integer
      Dim i As Integer = 0

      While i < Me.Lines.Length
         FirstVisibleChar = GetCharFromLineIndex(i)
         ColorLineNumber(i, FirstVisibleChar)
         i += 1
      End While
   End Sub

   Public Sub ColorVisibleLines()
      Dim FirstLine As Integer = FirstVisibleLine()
      Dim LastLine As Integer = LastVisibleLine()
      Dim FirstVisibleChar As Integer

      If (FirstLine = 0) And (LastLine = 0) Then
         'If there is no text it will error, so exit the sub
         Exit Sub
      Else
         While FirstLine < LastLine
            FirstVisibleChar = GetCharFromLineIndex(FirstLine)
            ColorLineNumber(FirstLine, FirstVisibleChar)
            FirstLine += 1
         End While
      End If

   End Sub

   Public Sub ColorLineNumber(ByVal LineIndex As Integer, ByVal lStart As Integer)
      Dim i As Integer = 0
      Dim Instance As Integer
      Dim LeadingChar, TrailingChar As String
      Dim SelectionAt As Integer = Me.SelectionStart
      Dim MyRow As DataRow
      Dim Line() As String, MyI As Integer, MyStr As String

      ' Lock the update
      LockWindowUpdate(Me.Handle.ToInt32)

      MyI = lStart

      If CaseSensitive Then
         Line = Split(Me.Lines(LineIndex).ToString, " ")
      Else
         Line = Split(Me.Lines(LineIndex).ToLower, " ")
      End If

      For Each MyStr In Line
         Me.SelectionStart = MyI
         Me.SelectionLength = MyStr.Length

         If Words.Rows.Contains(MyStr) Then
            MyRow = Words.Rows.Find(MyStr)
            If (Not CaseSensitive) Or (CaseSensitive And MyRow("Word") = MyStr) Then
               Me.SelectionColor = Color.FromName(MyRow("Color"))
            End If
         Else
            Me.SelectionColor = Color.Black
         End If

         MyI += MyStr.Length + 1
      Next

      ' Restore the selectionstart
      Me.SelectionStart = SelectionAt
      Me.SelectionLength = 0
      Me.SelectionColor = Color.Black

      ' Unlock the update
      LockWindowUpdate(0)
   End Sub

   Public Function GetCharFromLineIndex(ByVal LineIndex As Integer) As Integer
      Return SendMessage(Me.Handle, EditMessages.LineIndex, LineIndex, 0)
   End Function

   Public Function FirstVisibleLine() As Integer
      Return SendMessage(Me.Handle, EditMessages.GetFirstVisibleLine, 0, 0)
   End Function

   Public Function LastVisibleLine() As Integer
      Dim LastLine As Integer = FirstVisibleLine() + (Me.Height / Me.Font.Height)

      If LastLine > Me.Lines.Length Or LastLine = 0 Then
         LastLine = Me.Lines.Length
      End If

      Return LastLine
   End Function

   Public Sub New()
      Dim MyRow As DataRow
      Dim arrKeyWords() As String, strKW As String

      Me.AcceptsTab = True

      ''Load all the keywords and the colors to make them 
      Words.Columns.Add("Word")
      Words.PrimaryKey = New DataColumn() {Words.Columns(0)}
      Words.Columns.Add("Color")

      arrKeyWords = New String() {"select", "insert", "delete", _
         "truncate", "from", "where", "into", "inner", "update", _
         "outer", "on", "is", "declare", "set", "use", "values", "as", _
         "order", "by", "drop", "view", "go", "trigger", "cube", _
         "binary", "varbinary", "image", "char", "varchar", "text", _
         "datetime", "smalldatetime", "decimal", "numeric", "float", _
         "real", "bigint", "int", "smallint", "tinyint", "money", _
         "smallmoney", "bit", "cursor", "timestamp", "uniqueidentifier", _
         "sql_variant", "table", "nchar", "nvarchar", "ntext", "left", _
         "right", "like","and","all","in","null","join","not","or"}

      For Each strKW In arrKeyWords
         MyRow = Words.NewRow()
         MyRow("Word") = strKW
         MyRow("Color") = Color.LightCoral.Name
         Words.Rows.Add(MyRow)
      Next

   End Sub

   Public Property CaseSensitive() As Boolean
      Get
         Return _SyntaxHighlight_CaseSensitive
      End Get
      Set(ByVal Value As Boolean)
         _SyntaxHighlight_CaseSensitive = Value
      End Set
   End Property

Brian Tinkler is out in Redmond this weekend where he get to be one of the 5 judges for the national competition for software design for the Imagine Cup. This is awesome!

He is blogging about his experiences out there:

1. First Impressions from Redmond: http://geekswithblogs.net/btinkler/archive/2005/05/20/40095.aspx
2. He got to meet Scoble: http://geekswithblogs.net/btinkler/archive/2005/05/20/40146.aspx
3. 2Go Services: http://geekswithblogs.net/btinkler/archive/2005/05/21/40156.aspx
4. VS2005, then "Orkus", then "Hawaii": http://geekswithblogs.net/btinkler/archive/2005/05/21/40157.aspx

The Wisconsin .NET User Group and the Wisconsin development community in general is Representin'!

I ordered Visual Studio 2005 Beta 2 about 2 weeks ago, and I received it in the mail yesterday! The SQL Server 2005 CTP cam with it! I couldn't wait to install them and start playing. I didn't play around much with Beta 1; I just didn't make the point to spend much time with it (There are so many things to learn/do I can hardly find the time for it all.) One of the reasons I'm so excited about Beta 2 is because of the Go Live license (which you must go onlin and sign first; located here: http://lab.msdn.microsoft.com/vs2005/golive/). And so my journey began...

I uninstalled VS2005 Beta 1 and .NET Framework 2.0 Beta 1. Then I realized I forgot to uninstall Microsoft Visual J# .NET Redistributable Package 2.0 Beta, so I then uninstalled that. Then I started the Install of SQL Server 2005 CTP and go the following error:

Errors occurred during the installation:
Beta components detected.
Error 50266 installing .NET Framework 2.0

I then went and found that there were still 2.0 files on the drive and registry entries for them. So I made a copy of the files and registry entries (for backup) and then deleted the originals trying to manually uninstall the remaining .NET 2.0 Beta 1 components. To make a long story short, this didn't work so I had to restore the copies of these files.

After all that (took like 4 hours, I think) I searched Google and found this page: http://lab.msdn.microsoft.com/vs2005/uninstall

Apparently there is an exact order to uninstall the Beta 1 components in order to be able to install Beta 2. The part I screwed up with was I uninstalled the J# Redistributable Package 2.0 Beta 1 after I uninstalled .NET Framework 2.0 Beta 1.

Opps! I began wondering if I would need to reinstall Windows in order to get those bits off my machine so I could install Beta 2. Well, further down the page I saw this:

Notes:
1. If you see an erro removing J# .NET Redistributable Package 2.0 from Add/Remove Programs, please run “msiexec /x {9046F10C-F5E7-4871-BED9-8288F19C70DF}” from a command line window.
1. If you see an error removing .NET Framework 2.0 from Add/Remove Programs, please run “msiexec /x {71F8EFBF-09AF-418D-91F1-52707CDFA274}” from a command line window.

Wahoo! Exactly what I needed. I ran the part at the command lin to uninstall J# .NET Redistributable Package 2.0 and it worked like a charm. I am now successfully installing SQL Server 2005 CTP and Visual Studio 2005 Beta 2 while I type this post.