title: Remove whitespace within string
body: <p>I have strings like this:</p>
  <pre><code>&quot;This______is_a____string.&quot;
  </code></pre>
  <p>(The &quot;_&quot; symbolizes spaces.)</p>
  <p>I want to turn all the multiple spaces into only one. Are there any functions in C# that can do this?</p>