title: show/hide dropdown items based on previous dropdown selection
body: <p><strong>- - edited as i described it incorrectly first time round, sorry! - -</strong></p>
  
  <p>Hi,</p>
  
  <p>i am trying to use show/hide to manipulate what is shown in a second dropdown menu, based on what is selected in the first dropdown menu. However after having it work briefly, it now doesn't across any browser, it just shows them all no matter what is selected. <strong>When an option is selected in the first menu, it needs to then display particular options in the second menu.</strong> Each airport has it's own set of destinations. Unfortunately there isn't a php/mysql database option for this :/</p>
  
  <p>the js is as follows:</p>
  
  <pre><code>$(document).ready(function(){
  
  $("#from_BLANK").click(function () {
          $("#to_A1").show();
          $("#to_A2").show();
          $("#to_A3").show();
      });
      $("#from_A1").click(function () {
          $("#to_A1").hide();
          $("#to_A2").show();
          $("#to_A3").show();
      });
      $("#from_A2").click(function () {
          $("#to_A1").show();
          $("#to_A2").hide();
          $("#to_A3").show();
      });
      $("#from_A3").click(function () {
          $("#to_A1").show();
          $("#to_A2").show();
          $("#to_A3").hide();
      });
  });
  </code></pre>
  
  <p>And the html on the dropdowns is as follows:</p>
  
  <pre><code>&lt;select name="depApt" id="depApt"&gt;
      &lt;option id="from_BLANK" selected="selected"&gt;&amp;nbsp;&lt;/option&gt;
      &lt;option id="from_A1" value="A1"&gt;Airport One&lt;/option&gt;
      &lt;option id="from_A2" value="A2"&gt;Airport Two&lt;/option&gt;
      &lt;option id="from_A3" value="A3"&gt;Airport Three&lt;/option&gt;
  &lt;/select&gt;
  
  &lt;select name="dstApt" id="dstApt"&gt;
      &lt;option id="to_BLANK" selected="selected"&gt;&amp;nbsp;&lt;/option&gt;
      &lt;option id="to_A1" value="A1"&gt;Airport One&lt;/option&gt;
      &lt;option id="to_A2" value="A2"&gt;Airport Two&lt;/option&gt;
      &lt;option id="to_A3" value="A3"&gt;Airport Three&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>Are there any glaring errors? or maybe better ways to achieve this?</p>
  
  <p>Any and all help most appreciated!</p>
  
  <p>cheers,
  Paul</p>