void AddTextButton_Click (object sender, EventArgs e)
{
_richTextBox.Text = string.Format (CultureInfo.InvariantCulture,
"Some Text That Should Allow Us To Test Both Vertical And " +
"Horizontal Scrollbars, And The Effect Of WordWrap.{0}{0}" +
"Line #1{0}{0}" +
"Line #2{0}{0}" +
"Line #3{0}{0}" +
"Line #4{0}{0}" +
"Line #5{0}{0}" +
"Line #6{0}{0}" +
"Line #7{0}{0}" +
"Line #8{0}{0}" +
"Line #9{0}{0}",
Environment.NewLine);
}