fontDialog-字体对话框和colorDialog-颜色对话框

 private void button1_Click(object sender, EventArgs e)

        {

            DialogResult dr = fontDialog1.ShowDialog();//显示选择字体对话框

            if (dr == DialogResult.OK)//确认是否按下了确定按钮

            {

                richTextBox1.SelectionFont = fontDialog1.Font;//设置richtextbox中文本的字体

            }

        }

private void button1_Click(object sender, EventArgs e)

        {

            DialogResult dr = colorDialog1.ShowDialog();//显示选择文字颜色对话框

            if (dr == DialogResult.OK)//确认是否按下了确定按钮

            {

                richTextBox1.SelectionColor = colorDialog1.Color;//设置richtextbox中文本的字体

            }

        }