Rich Text Box padding between text and border

Question

Is it possible to add padding into a Rich Text Box control between the text and the border?

I tried docking a rich text box inside of a panel, with its padding for all f

Answer 1

Here's an even easier answer. It's not customizable, but it will put a small padding around the entire text -- top, bottom, left and right.

At design time, set the ShowSelectionMargin property of the RichTextBox to True. When you run, you might notice the margin being applied (from no margin to margin), which looks a little "jerkey". If so, put a Me.SuspendLayout in front of loading the RichTextBox, and put a Me.ResumeLayout after.

Answer 2

I had this same problem and the answer described didn't help me, this worked for me so i'll share it if it helps.

richTextBox1.SelectAll();
richTextBox1.SelectionIndent += 15;//play with this values to match yours
richTextBox1.SelectionRightIndent += 15;//this too
richTextBox1.SelectionLength = 0;
//this is a little hack because without this
//i've got the first line of my richTB selected anyway.
richTextBox1.SelectionBackColor = richTextBox1.BackColor;

Answer 3

Set the padding on the right to 0, and then set the RightMargin of the RichTextBox to 10. Not tested, but should work.

Answer 4

Perhaps you are looking to indent text? Like left and right indent? If so, then you could just use ReGEtIndent and ReSetIndent methods of the rtf object.

Here what I do:

//first I find the length of the active window

nLen := REGEtIndent( ::oActive:hWnd )    
//now resetIndents of the rtf control    
RESetIndent( ::oActive:hWnd, nLen[ 1 ] + 100, nLen[ 2 ] + 100, -25 )

Hope that helps.

Answer 5

Since RichTextBox has no padding property. You can create your own RichTextBoxSubclass like the one in this article:

http://www.codeproject.com/Articles/21437/A-Padded-Rich-Text-Box-Subclass

Answer 6

There are EM_GETRECT and EM_SETRECT.

Combining those two together, you can make this:

…look like this:

I've written a small C# extension class to wrap this all up.

Usage example:

const int dist = 24;
richTextBox1.SetInnerMargins(dist, dist, dist, 0);

This sets the inner margins left, top and right to 24, leaving the bottom as zero.

Please note that when scrolling, the top margin stays as being set, giving something like this:

Personally, this looks "unnatural" to me. I would prefer that when scrolling the top margin becomes zero, too.

Maybe there is a workaround for that…

Full source code

As of request:

public static class RichTextBoxExtensions
{
    public static void SetInnerMargins(this TextBoxBase textBox, int left, int top, int right, int bottom)
    {
        var rect = textBox.GetFormattingRect();

        var newRect = new Rectangle(left, top, rect.Width - left - right, rect.Height - top - bottom);
        textBox.SetFormattingRect(newRect);
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct RECT
    {
        public readonly int Left;
        public readonly int Top;
        public readonly int Right;
        public readonly int Bottom;

        private RECT(int left, int top, int right, int bottom)
        {
            Left = left;
            Top = top;
            Right = right;
            Bottom = bottom;
        }

        public RECT(Rectangle r) : this(r.Left, r.Top, r.Right, r.Bottom)
        {
        }
    }

    [DllImport(@"User32.dll", EntryPoint = @"SendMessage", CharSet = CharSet.Auto)]
    private static extern int SendMessageRefRect(IntPtr hWnd, uint msg, int wParam, ref RECT rect);

    [DllImport(@"user32.dll", EntryPoint = @"SendMessage", CharSet = CharSet.Auto)]
    private static extern int SendMessage(IntPtr hwnd, int wMsg, IntPtr wParam, ref Rectangle lParam);

    private const int EmGetrect = 0xB2;
    private const int EmSetrect = 0xB3;

    private static void SetFormattingRect(this TextBoxBase textbox, Rectangle rect)
    {
        var rc = new RECT(rect);
        SendMessageRefRect(textbox.Handle, EmSetrect, 0, ref rc);
    }

    private static Rectangle GetFormattingRect(this TextBoxBase textbox)
    {
        var rect = new Rectangle();
        SendMessage(textbox.Handle, EmGetrect, (IntPtr) 0, ref rect);
        return rect;
    }
}