title: if string item is not in string array
body: <p>I have a string array.
  I need to display buttons based on if the selected item is in the array.
  I need to know how to tell the program if "(array.<strong>NOT</strong> Contains("string"))".
  Please can anybody help me??
  Thanks in advance</p>
  
  <p>My code:</p>
  
  <pre><code>    List&lt;string&gt; activationids = new List&lt;string&gt;();
      foreach (ModuleActivation moduleactivation in activationid)
           activationids.Add(moduleactivation.ActivationID);
  
      string gvselectActID = GridView1.SelectedRow.Cells[1].Text;
  
      if (activationids.Contains(gvselectActID))
      {
        activateInsert.Visible = true;
        activateUpdate.Visible = false;
        deactivate.Visible = true;
      }
      else if (activationids."NOT" Contains(gvselectActID))
      {
        activateInsert.Visible = false;
        activateUpdate.Visible = true;
        deactivate.Visible = false;
      }
      else
      {
       activateInsert.Visible = false;
       activateUpdate.Visible = false;
       deactivate.Visible = false;
      }
    } 
  </code></pre>