Question

I know a good amount of PHP, but know very little of Javascript.

Basically, what I want is:

If a user selects item x from an HTML form select box, then the descriptive text for item x will auto populate an HTML form input text box below it.

Does anyone have a working sample that I can use or edit to be able to do what I need?

Answer 1

Here is a working copy in plain JavaScript using no libraries:

<script type="text/javascript">
    // Pre populated array of data
    var myData = new Array();
    myData[1] = 'Some text';
    myData[2] = 'Some other text';
</script>     
<form id="example" name="example">
        <select id="selector" name="selector">
            <option value="" selected></option>
            <option value=1>One</option>
            <option value=2>Two</option>
        </select>
        <br />
        <input type="text" value="" id="populateme" name="populateme" />
    </form>

    <script type="text/javascript">
        document.example.selector.onchange = updateText;

        function updateText() {
          var obj_sel = document.example.selector;
          document.example.populateme.value = myData[obj_sel.value];
    }
    </script>