title: Select All Checkbox
body: <p>I have a webpage that returns search results in a table/form.  I would like to have a select all checkbox, that would select all the checkboxes for the search results.  My code for the display results is below:</p>
  
  <pre><code>&lt;form action="noJavaScript.php" name="theForm" method="post"&gt;
  &lt;table style="border: 1px solid black" RULES=ALL FRAME=VSIDES&gt;
  &lt;th&gt; &lt;/th&gt;&lt;th&gt;Order #&lt;/th&gt;&lt;th&gt;Inspector&lt;/th&gt;&lt;th&gt;Reference #&lt;/th&gt;&lt;th&gt;Client Name&lt;/th&gt;&lt;th&gt;Property Address&lt;/th&gt;&lt;th&gt;City&lt;/th&gt;&lt;th&gt;State&lt;/th&gt;&lt;th&gt;Zip&lt;/th&gt;&lt;th&gt;Inspection Date&lt;/th&gt;
          &lt;?php
              while ($row = mysql_fetch_assoc($result))
              {
                  echo '&lt;tr&gt;&lt;td&gt;';
                  echo '&lt;input type="checkbox" name="selected[]" value="'.$row['order_number'].'"/&gt;';
                  echo '&lt;/td&gt;';
                  foreach ($row as $key =&gt; $value)
                      echo '&lt;td&gt;'.htmlspecialchars($value).'&lt;/td&gt;';
                  echo '&lt;/tr&gt;';
              }
          ?&gt;
  
      &lt;/table&gt;
  &lt;input type="submit" name="submit" value="Edit/Modify Order" onClick="document.theForm.action='modify.php'"&gt;
  &lt;input type="submit" name="submit" value="Clone Order" onClick="document.theForm.action='clone.php'"&gt;
  &lt;input type="submit" name="submit" value="Delete Order" onClick="document.theForm.action='deleteorder.php'"&gt;
  &lt;input type="submit" name="submit" value="Archive Order" onClick="document.theForm.action='archive.php'"&gt;
  
  &lt;/form&gt;
  </code></pre>
  
  <p>I have tried using the following function:</p>
  
  <pre><code>&lt;script type="text/javascript"
  &lt;!--
  function SetAllCheckBoxes(FormName, FieldName, CheckValue)
  {
      if(!document.forms[FormName])
          return;
      var objCheckBoxes = document.forms[FormName].elements[FieldName];
      if(!objCheckBoxes)
          return;
      var countCheckBoxes = objCheckBoxes.length;
      if(!countCheckBoxes)
          objCheckBoxes.checked = CheckValue;
      else
          // set the check value for all check boxes
          for(var i = 0; i &lt; countCheckBoxes; i++)
              objCheckBoxes[i].checked = CheckValue;
  }
  // --&gt;
  &lt;/script&gt;
  </code></pre>
  
  <p>And the button like this:</p>
  
  <pre><code>        &lt;input type="button" onclick="SetAllCheckBoxes('theForm', 'myCheckbox', true);" value="Check All"&gt;;
  </code></pre>
  
  <p>But I can't get it to work.</p>