title: what is the equivalent Range Function (VBA) in C#
body: <p>I am in an process migration VBA to C#. I do not know how to use or what is the equivalent in C#. Let me show you the line of code:</p>
  
  <pre><code>Range("U1:U" &amp; LastRow).FormulaR1C1 = "=if(rc[-1]=""" &amp; qyyyy &amp; """,rc[-15],rc[-14])"
  </code></pre>