What is the meaning of NullReferenceException
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  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-in-net">What is a NullReferenceException in .NET?</a>  </p>
</blockquote>



<p>For example, "<code>System.NullReferenceException</code> was unhandled", with Message "Object reference not set to an instance of an object."</p>

<p>What is the meaning of this exception, and how can it be solved?</p>
