title: IsNullorEmpty combobox.selectedvalue
body: <p>I am trying to set a combobox.selectedValue to a string which works but when its nullorempty it errors out.  I have tried the following code to no avail:</p>
  
  <pre><code>        if (string.IsNullOrEmpty(docRelComboBox.SelectedValue.ToString()))
          {
              document = "other";
          }
  
          else
          {
              document = docRelComboBox.SelectedValue.ToString();
          }
  </code></pre>
  
  <p>The combobox is databound but in theory it could be nullorempty in certain situations and I need to be able to pass the other value at those times.  Any help would be great.</p>