How to group digits and remove trailing zeros

[SAWULA]

I am making a c# calculator, and I want group the digits and remove trailling zeros.

whan I uesed this code

NumberFormatInfo nFI = new CultureInfo("en-US",false).NumberFormat;
Decimal int_value = Decimal.Parse(textBox1.Text);

It displays only two decimal digits. If it is not decimal fraction it dispalys two zeros.