Question

I’m using VS2010, C# to develop a WinForm application, is there a way to use two fonts in a textbox? for instance my user is typing with Tahoma font, then he can press a key combination or click on a button and he can type with Times New Roman font (text typed with Tahoma should not change its font)

what are my options? I suppose RichTextBox is my only options, is it right? if so, how can I remove RichTextBox icons and toolbars?

what about Telerik or other third party components?

Answer 1

As you say, RichTextBox will help you doing what you ask for. However, I do not understand your statement about removing icons and toolbars. The contrary is true, you will have to create your own buttons in order to enable formatting.

As an example I show you how can toggle the bold style of the selection

private void boldToolStripButton_Click(object sender, EventArgs e)
{
    ToggleFontStyle(FontStyle.Bold);
    boldToolStripButton.Checked = !boldToolStripButton.Checked;
}

private void ToggleFontStyle(FontStyle style)
{
    int selStart = richTextBox.SelectionStart;
    int selLength = richTextBox.SelectionLength;
    int selEnd = selStart + selLength;

    if (selLength == 0) {
        return;
    }

    Font selFont = richTextBox.SelectionFont;
    if (selFont == null) {
        richTextBox.Select(selStart, 1);
        selFont = richTextBox.SelectionFont;
        if (selFont == null) {
            return;
        }
    }
    bool set = (selFont.Style & style) == FontStyle.Regular;

    for (int from = selStart, len = 1; from < selEnd; from += len) {
        richTextBox.Select(from, 1);
        Font refFont = richTextBox.SelectionFont;
        for (int i = from + 1; i < selEnd; i++, len++) {
            richTextBox.Select(i, 1);
            if (!refFont.Equals(richTextBox.SelectionFont))
                break;
        }
        richTextBox.Select(from, len);
        if (set) {
            richTextBox.SelectionFont = new Font(refFont, refFont.Style | style);
        } else {
            richTextBox.SelectionFont = new Font(refFont, refFont.Style & ~style);
        }
    }
    // Restore the original selection
    richTextBox.Select(selStart, selLength);
}

As you can see this is quite complicated, since the current text selection can contain text parts that are formatted differently. This code changes the font style in a piece-wise manner, ensuring that a piece has a unique format.

In order to provide a user friendly interface you also will have to treat text selection events and to toggle the style buttons according to the formatting of the selection. I.e. if the user selects a bold text, then the bold-toggle-button should be in the pressed-state.