Question

For example, the select box

<select>
  <option selected="" value="">Please Select</option>
  <option value='txt'>Text</option>
  <option value='int'>Numbers</option>
  <option value='bool' >Boolean</option>
</select>

has a string

$messageList=array ( 'txt'=>'text message', 'int'=>'int message',
                     'bool'=>'bool message');

What i would like to achieve is to display correspond message when the optition is select?

Answer 1

I don’t know php, but First I think you need to use json_encode to convert php array to a javascript object. http://php.net/manual/en/function.json-encode.php

<?php
   $messageList=array ( 'txt'=>'text message', 'int'=>'int message','bool'=>'bool message');

   echo var msgs = json_encode($messageList);
?>

And then in javascript,

$('select').change (function () { 
    alert(msgs[$(this).val()]);
});

Also you need a class/id for the select. because the above code will triggered when you change the option of any select box in the page.