title: Linq query to check substring between a list and string
body: <p>I have a list of strings and a string, and I want that if the string contains any of the string which is present in the list the system returns false. I am using following lambda expression:</p>
  
  <pre><code> result = !(((string[])ro_operandVal).ToList&lt;string&gt;()).Any(x =&gt; x.ToString().ToUpper() == lo_operandVal.ToString().ToUpper());
  </code></pre>
  
  <p>Following is the dataset:</p>
  
  <p>lo_operandVal = "ABC DEF GHI Post Office Box"
  ro_operandVal is the list of strings with following elements:</p>
  
  <ol>
  <li>Post Office Box </li>
  <li>P.O. BOX</li>
  </ol>
  
  <p>when I evaluate this expression it always returns true.</p>