Error while increasing the font size.

[blackaly]

Hi bro. I was learning from your project, and I found a bug while increasing the font size from the increaseStripButton_Click().

Solution:

private void increaseStripButton_Click(object sender, EventArgs e)
        {
            try
            {
                int size = Convert.ToInt32(richTextBox1.SelectionFont.Size) + 1;    // convert (fontSizeNum + 1)
                if (richTextBox1.SelectionFont == null)
                {
                    return;
                }
                // sets the updated font size
                richTextBox1.SelectionFont = new Font(richTextBox1.SelectionFont.FontFamily
                    ,size,richTextBox1.SelectionFont.Style);

                fontSizeComboBox.Text = size.ToString();    // update font size
            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.Message, "Error Information", MessageBoxButtons.OK, 
                    MessageBoxIcon.Warning); // show error message
            }
        }

Good luck!