Could I use Ajax to preload a dropbox?

superthin · 11-25-2008, 01:18 AM

Hello all,

I have got a html form to input books' information. When I run my PHP script in localhost, everthing is good. The problem is when I upload it to my shared hosting, the hosting provider tells me that my script consumes a lot of server's resources.

My friend told me that I should use Ajax to pre-load dropbox(es). I don't know how to do that.

I want to "Choose a language" (1) it will have an influence on "Choose an author" (2) and "Choose a publisher" (3). That means "When I choose French, American authors and publishers will not to be listed".

I am using an "onchange" event in HTML to refresh / reload. It makes a slow flicker, a long delayed time, a lot of hosting resource,...

Some queries with Google and Altavista I cannot solve the problem. Will everybody here tell me what Ajax tool(s) I should use?

Thanks in advance.

Best regards,

martins256 · 11-25-2008, 09:13 AM

It's easy with jquery! I'll make an example for you:

some place in your form

HTML Code:

<select name="authors" id="authors" >
<option value="1">French</option>
<option value="2">American</option>
</select>

<select name="publisher" id="publisher" ></select>

JS to do all the ajax magic(I use jquery so you will need that to try my example too).

HTML Code:

$(document).ready(function(){
  $("#authors").change(function(){
    id = $("#authors").val();
    $("#publisher").load("ajax.publisher.php?id="+id);
  });
});

And the "ajax.publisher.php"

PHP Code:


			
<?php

session_start();

error_reporting(E_ALL);



include('config.php');

include('functions.php');



if(isset($_GET['id']) and ctype_digit($_GET['id']))

{

  $sql = "SELECT * FROM publishers WHERE author_id = {$_GET['id']}";

  $result = mysql_query($sql);

  while($row = mysql_fetch_assoc($result))

  {

    echo '<option value="'.$row['id'].'">'.$row['publisher'].'</option>';

  }

}

?>

superthin · 11-25-2008, 04:57 PM

Oh, thank martins256 very much. I would like to say "You are a star" :)