title: String.Format decimal with both thousand separators and forced decimal places
body: <p>I'd like to <code>String.Format</code> a decimal so that it has both thousand separators and forced decimal places (3).</p>
  
  <p>For example:</p>
  
  <p>Input:</p>
  
  <pre><code>123456,12
  78545,8
  </code></pre>
  
  <p>Output:</p>
  
  <pre><code>123.456,120
  78.545,800
  </code></pre>
  
  <p>I have tried </p>
  
  <pre><code>String.Format("{0:0.0,000}", input);
  </code></pre>
  
  <p>but this only gives the thousand separators but doesn't <strong>force</strong> the decimal places.</p>