c# how to String.Format decimal with unlimited decimal places?
<p>I need to convert a decimal number to formatted string with thousand groups and unlimited (variable) decimal numbers:</p>

<pre>

    1234 -> "1,234"
    1234,567 -> "1,234.567"
    1234,1234567890123456789 -> "1,234.1234567890123456789"

</pre>

<p>I tried <b>String.Format("{0:#,#.#}", decimal)</b>, but it trims any number to max 1 decimal place.</p>
