Code Editor similiar to Visual Studio 2005..

[tMacK]

I am designing a script editor in C#. For some reason, I just cannot figure out how to properly use the Rich Text Box control properly. I want my code editor to look similar to Visual Studio's code editor. I can do syntax highlighting, what I need to know is how to add line counting on the left side in the same control.

If I try to use a separate control to add line counts, the problem occurs with scrolling. Here is what I want:

.

All I basically want is the line counting, nothing else. I already wrote the code to count lines.. I just can't accomplish that one thing!

Thanks!

[tMacK]

So, does anyone have a good idea?

[AIS4U]

tMack:

Well, 35 people have viewed your posting and no one has posted any possible solution, so I guess we don't know.

However, I have a real long shot that might work. I can't tell you exactly how to make it work, but maybe you can figure it out or someone else can tell you.

MSWord has a template that is used when you want to write legal pleading. This template has the numbers down the left side and you can set the numbers to be whatever you want.
I don't know if the template would be in the MSWord Object or in a dll or where it would be, but if you could figure out how to hook into that template it should give you exactly what you need.
Maybe if you posted in the section for Microsoft Office someone could tell you how to hook up to it.
Hack seem to be the resident Office Expert.
Good Luck

[tMacK]

Sounds like a idea, but I found some code to synchronize the positions in a text box. It's VBNET though, so I have to convert it.. but if anyone has any more ideas hit me up.

[minor28]

I while ago I have written an editor with line numbers in VB6 (and also assembler). This is how you do it.

First subclass the richtextbox window process and catch the WM_PAINT message

If uMsg = WM_PAINT Then
    SendMessage hwnd, EM_GETRECT, 0, rt
    rt.Left = 36
    SendMessage hwnd, EM_SETRECT, 0, rt
    DrawLineNumbers hwnd
End If

The DrawLineNumbers function is like this

Private Sub DrawLineNumbers(ByVal hWin As Long)
    Dim lineno As Long
    Dim linecount As Long
    Dim buffer(32) As Byte
    Dim hdc As Long
    Dim rt As RECT
    Dim hRgn As Long
    Dim hObjRgn As Long
    Dim hObjFont As Long
    Dim hObjStock As Long
    Dim fheight As Long
    
    GetUpdateRect hWin, rt, False
    If rt.Left < 28 Then
        rt.Right = 28
        ValidateRect hWin, rt
    End If
    hdc = GetDC(hWin)
    SetBkMode hdc, TRANSPARENT
    hRgn = CreateRectRgn(rt.Left, rt.Top, rt.Right, rt.Bottom)
    hObjRgn = SelectObject(hdc, hRgn)
    hObjFont = SelectObject(hdc, hFont)
    lineno = SendMessage(hWin, EM_GETFIRSTVISIBLELINE, 0, 0) + 1
    GetClientRect hWin, rt
    rt.Right = 28
    hObjStock = GetStockObject(LTGRAY_BRUSH)
    FillRect hdc, rt, hObjStock
    linecount = SendMessage(hWin, EM_GETLINECOUNT, 0, 0)
    Do While linecount >= lineno
        fheight = DrawText(hdc, lineno, -1, rt, DT_RIGHT Or DT_TOP)
        rt.Top = rt.Top + fheight
        lineno = lineno + 1
    Loop
    SelectObject hdc, hObjFont
    SelectObject hdc, hObjStock
    ReleaseDC hWin, hdc

End Sub

In the Form load event I choose font and retrieved the font handle

Private Sub Form_Load()
    Dim lfont As LOGFONT
    
    Me.RichTextBox1.Font.Name = "Courier New"
    Me.RichTextBox1.Font.Size = 10
    hFont = CreateFontIndirect(lfont)
End Sub

This code will generate a gray field to the left with black numbers.

I would appreciate if you publish your result in C# code.

[sunburnt]

I would look at the Code Editor component of SharpDevelop -- they seem to have this feature along with a lot of others.

[minor28]

This works. If you want another color just change the brush. If you want a vertical line you must draw it.

Subclassed richtextbox window process

protected override void WndProc(ref Message m)
{
    if (m.Msg == WM_PAINT)
    {
        RECT rt = new RECT();
        GCHandle gch = GCHandle.Alloc(rt);
        SendMessage(this.Handle, EM_GETRECT, 0, (IntPtr)gch);
        rt = (RECT)Marshal.PtrToStructure((IntPtr)gch, typeof(RECT)); 
        rt.Left = 36;
        Marshal.StructureToPtr(rt, (IntPtr)gch, false);
        SendMessage(this.Handle, EM_SETRECT, 0, (IntPtr)gch);
        gch.Free();
        DrawLineNumber(this.Handle);
    }
    base.WndProc(ref m);
}

DrawLineNumber function

private void DrawLineNumber(IntPtr hwnd)
{
    RECT rt = new RECT();
    GetUpdateRect(hwnd, out rt, false);
    if (rt.Left < 28)
    {
        rt.Right = 28;
        ValidateRect(hwnd, ref rt);
    }
    IntPtr hDC = GetDC(hwnd);
    SetBkMode(hDC, TRANSPARENT);
    IntPtr hRgn = CreateRectRgn(rt.Left, rt.Top, rt.Right, rt.Bottom);
    IntPtr hObjRgn = SelectObject(hDC, hRgn);
    IntPtr hObjFont = SelectObject(hDC, this.Font.ToHfont());
    int lineno = SendMessage(hwnd, EM_GETFIRSTVISIBLELINE, 0, IntPtr.Zero) + 1;
    GetClientRect(hwnd, out rt);
    rt.Right = 28;
    IntPtr hObjStock = GetStockObject(LTGRAY_BRUSH);
    FillRect(hDC, ref rt, hObjStock);
    int linecount = SendMessage(hwnd, EM_GETLINECOUNT, 0, IntPtr.Zero);

    do
    {
        int fheight = DrawText(hDC,lineno.ToString(),-1,ref rt,DT_RIGHT + DT_TOP);
        rt.Top = rt.Top + fheight;
        lineno = lineno + 1;
    }
    while (linecount>=lineno);
    SelectObject(hDC, hObjFont);
    SelectObject(hDC, hObjStock);
    ReleaseDC(hwnd, hDC);
}

[tMacK]

Thanks guys. I appreciate it! At least now I got something to work with.