title: NOT IN in SSRS TextBox
body: <p>How can I write <code>NOT IN</code> in TextBox expression?</p>
  
  <p>I must check if some field value not belong to some list of strings, and then do some work.</p>
  
  <p>Example:</p>
  
  <pre><code>Iif(SomeField.Value NOT IN ('Text1', 'Text2'), DoSomething, nothing)
  </code></pre>
  
  <p>I wrote code like this and got error when previewing report, and error was :</p>
  
  <pre><code>Overload resolution failed because no accessible 'Iif' accepts this number of type arguments
  </code></pre>
  
  <p>How can I do this stuff?</p>