Javascript：函数doScan（代码）链接到php文件，用于搜索mysql

I'm a newbie on php, javascript and ajax. I got this tutorial about How to Create a Search Feature with PHP and MySQL and it was a success after creating it. Link: http://www.webreference.com/programming/php/search/index.html

Now I'm changing the index.html file and linked only to search_display.php file for just a simple price checker program. I was confuse on how to link the "code" result under Javascript function doScan(code) to search_display.php.

<script>
   function doScan(code) //displays the value target after scanning.
   {
      divStatus.innerHTML = 'Scanned Code:<br>&nbsp;&nbsp;' + code;
      setTimeout("startScanner()", 1250);
   }
</script>

I wanted to link "code" to search_display.php and this is the code:

<?php
  if(isset($_POST['submit'])){
  if(isset($_GET['go'])){
  //if(preg_match("/^[a-zA-Z]+/", $_POST['name'])){
  $name=$_POST['name'];
  //connect to the database
  $db=mysql_connect("localhost", "root", "bbp0m") or die ('I cannot connect to the database  because: ' . mysql_error());
  //var_dump($db);
  //-select the database to use
  $mydb=mysql_select_db("price_checker");
  //var_dump($mydb);
  //-query the database table
  $sql="SELECT * FROM stock_master WHERE gtin LIKE '%" . @$name .  "%'";
  //var_dump($sql);
  //-run the query against the mysql query function
  $result=mysql_query($sql);
  //var_dump($result);
  //-create while loop and loop through result set
  while($row=mysql_fetch_array($result)){
          $itemcode=$row['itemcode'];
          $desc1=$row['desc1'];
          $desc2=$row['desc2'];
          $uom=$row['uom'];
          $gtin=$row['gtin'];
          $retailprice=$row['retailprice'];
  //-display the result of the array
  echo "<ul>
";
  echo "<li>" . "<a  href=\"index.html?id=$gtin\">" .$itemcode . " " . $desc1 . " " . $desc2 . " " . $uom . " " . $gtin . " " . $retailprice . "</a></li>
";
  echo "</ul>";
  }
  }
  else{
  echo  "<p>Please enter a search query</p>";
  }
  }
  //}
?>

Any ideas how to link it and if possible I would like to put everything into index.html?

Bert