Change font using C # font dialog

Question

Can someone tell me how I can change the font using the font dialog. I am trying to make sure that either the selected text changes or the text is not selected only in the font after changing the marker (not in the whole text field).

This is what I still have. Thanx

 private void menuFont_Click(object sender, EventArgs e)
    {
        if (fontDialog1.ShowDialog() == DialogResult.OK)
        {
            if (richtextbox.SelectedText != "")
            {
                richtextbox.Font = fontDialog1.Font;
            }
    }}

Answer 1

private void menuFont_Click(object sender, EventArgs e)
{
  if (fontDialog1.ShowDialog() == DialogResult.OK & !String.IsNullOrEmpty(richtextbox.Text))
  {
      richtextbox.SelectionFont = fontDialog1.Font;
  }
  else
  {
     //  richtextbox.SelectionFont = ?
  }
} 

---

EDIT:

you can use &&if fontDialog1.ShowDialog() == DialogResult.OK- false, and this condition alone satisfies the condition of use for else, as user210118recommended

Answer 2

SelFont, SelX, ? , , , SelectedX, .

Answer 3

Use the SelectionFont RichTextBox property , the example will work as you need:

private void menuFont_Click(object sender, EventArgs e)
{
    if (fontDialog1.ShowDialog() == DialogResult.OK) {
        richtextbox.SelectionFont = fontDialog1.Font;
    }
}

Answer 4

To get the next text entered as a different font, and not just the selected text, you need to add a run block in RTB and then write to it. I applied a toolbar for RTB that does something like this:

    public static void SetFontSize(RichTextBox target, double value)
    {
        // Make sure we have a richtextbox.
        if (target == null)
            return;

        // Make sure we have a selection. Should have one even if there is no text selected.
        if (target.Selection != null)
        {
            // Check whether there is text selected or just sitting at cursor
            if (target.Selection.IsEmpty)
            {
                // Check to see if we are at the start of the textbox and nothing has been added yet
                if (target.Selection.Start.Paragraph == null)
                {
                    // Add a new paragraph object to the richtextbox with the fontsize
                    Paragraph p = new Paragraph();
                    p.FontSize = value;
                    target.Document.Blocks.Add(p);
                }
                else
                {
                    // Get current position of cursor
                    TextPointer curCaret = target.CaretPosition;
                    // Get the current block object that the cursor is in
                    Block curBlock = target.Document.Blocks.Where
                        (x => x.ContentStart.CompareTo(curCaret) == -1 && x.ContentEnd.CompareTo(curCaret) == 1).FirstOrDefault();
                    if (curBlock != null)
                    {
                        Paragraph curParagraph = curBlock as Paragraph;
                        // Create a new run object with the fontsize, and add it to the current block
                        Run newRun = new Run();
                        newRun.FontSize = value;
                        curParagraph.Inlines.Add(newRun);
                        // Reset the cursor into the new block. 
                        // If we don't do this, the font size will default again when you start typing.
                        target.CaretPosition = newRun.ElementStart;
                    }
                }
            }
            else // There is selected text, so change the fontsize of the selection
            {
                TextRange selectionTextRange = new TextRange(target.Selection.Start, target.Selection.End);
                selectionTextRange.ApplyPropertyValue(TextElement.FontSizeProperty, value);
            }
        }
        // Reset the focus onto the richtextbox after selecting the font in a toolbar etc
        target.Focus();
    }