title: Convert VB.net DateAdd into C#
body: <p>I am not able to find the right way to convert <code>DateAdd</code> to C#. I tried Telerik and other tools to convert nothing is correct. All giving compile errors.</p>
  <pre class="lang-vb prettyprint-override"><code>dtDueDate = DateAdd(DateInterval.WeekOfYear, intFreqInMonths * intIndex, nextPaymentDueDate)
  dtDueDate = DateAdd(&quot;m&quot;, 1, dtDueDate)
  dtDueDate = DateAdd(&quot;m&quot;, intFreqInMonths * intIndex, nextPaymentDueDate)
  </code></pre>
  <h2>Telerik</h2>
  <pre class="lang-cs prettyprint-override"><code>dtDueDate = DateTime.DateAdd(DateInterval.WeekOfYear, intFreqInMonths * intIndex, nextPaymentDueDate);
  dtDueDate = DateTime.DateAdd(&quot;m&quot;, 1, dtDueDate);
  dtDueDate = DateTime.DateAdd(&quot;m&quot;, intFreqInMonths * intIndex, nextPaymentDueDate);
  </code></pre>