textbox.style c# format code example
Example: how to format textbox thousand separator
textBox1.Text = string.Format(System.Globalization.CultureInfo.GetCultureInfo("id-ID"), "{0:#,##0.00}", double.Parse(textBox1.Text));
textBox1.Text = string.Format(System.Globalization.CultureInfo.GetCultureInfo("id-ID"), "{0:#,##0.00}", double.Parse(textBox1.Text));