title: Formatting string - money value
body: <p>I'm trying to format my <code>double</code> to be in US dollar currency format, but I do not want trailing <code>00</code>'s if the value comes out to be a whole number.</p>
  
  <p>I have tried</p>
  
  <pre><code>String.Format("{0:#,0.#0}", cost);
  </code></pre>
  
  <p>and </p>
  
  <pre><code>String.Format("{0:#,0.##}", cost);
  </code></pre>
  
  <p>The former is leaving me trailing <code>00</code> on whole number, and the latter is will give me <code>55.6</code> where I want <code>55.60</code>. How can I format my value to meet both of these needs?</p>