title: how can I remove zeros from exponent notation
body: <p>I'm using exponential formatting to format a decimal number in C#. 
  For example if the number is </p>
  
  <pre><code>0.0001234567
  </code></pre>
  
  <p>Formatting with </p>
  
  <pre><code>(0.0000123456).ToString("E4");
  </code></pre>
  
  <p>Shows </p>
  
  <pre><code>1.2345E-004
  </code></pre>
  
  <p>How can I remove leading zero from exponent so it read as below?</p>
  
  <pre><code>1.2345E-4
  </code></pre>