title: Regex.Match whole words
body: <p>In <code>C#</code>, I want to use a regular expression to match any of these words:</p>
  
  <pre><code>string keywords = "(shoes|shirt|pants)";
  </code></pre>
  
  <p>I want to find the whole words in the content string.  I thought this <code>regex</code> would do that:  </p>
  
  <pre><code>if (Regex.Match(content, keywords + "\\s+", 
    RegexOptions.Singleline | RegexOptions.IgnoreCase).Success)
  {
      //matched
  }
  </code></pre>
  
  <p>but it returns true for words like <code>participants</code>, even though I only want the whole word <code>pants</code>.  </p>
  
  <p>How do I match only those literal words?</p>