PHP $ _POST请求无效

Question

I have a drop down list in a html document, the options in the drop down are obtained via a PHP GET request, with Ajax populating the HTML document (Done on page load). The purpose of the drop down is to select an option, click the button, where the map will zoom to the extent. However the POST request for the selected option doesn't return anything.

Is there any reason for this?

HTML

<form id="form" method="post" action="php/zoom.php">
      <select id="selectProp" name="selectProp">
          <optgroup class="zoomProp_OG" id ="zoom">
          </optgroup>
      </select>
      <input type="button" value="Zoom to property" onClick="zoomToProp()">
 </form>

PHP

$attribute = $_POST['selectProp'];

Answer 1

<input type="button"> is for a button that doesn't do anything (unless you hang JavaScript off it). Your form isn't being submitted so there is no POST request and the PHP doesn't run..

You need <input type="submit"> (or Ajax).