title: How to check empty DataTable
body: <p>I have a <code>DataSet</code> where I need to find out how many rows has been changed using the following code:</p>
  
  <pre><code>dataTable1 = dataSet1.Tables["FooTable"].GetChanges();
  
  foreach (DataRow dr in dataTable1)
  {
    // ...
  }
  </code></pre>
  
  <p><code>DataSet</code> has <code>DataSet.HasRow</code> but <code>DataTable</code> doesn't have such method. If there is no changed rows. <strong>changedDT1</strong> will be a null value, causing the loop to throw exception.</p>
  
  <p>How do I check if <code>DataTable</code> is empty? I tried <code>Rows.Count</code> - doesn't work...</p>