Code help. Reload to same page when hit submit button

<?php session_start();
 
?>
 
<?php
  $conn = connect();
  $showrecs = 20;
  $pagerange = 10;
 
  $a = @$_GET["a"];
  $recid = @$_GET["recid"];
  $page = @$_GET["page"];
  if (!isset($page)) $page = 1;
 
  $sql = @$_POST["sql"];
 
  switch ($sql) {
    case "update":
      sql_update();
      break;
  }
 
  switch ($a) {
    case "edit":
      editrec($recid);
      break;
    default:
      select();
      break;
  }
 
 
  mysql_close($conn);
?>
<table class="bd" width="100%"><tr><td class="hr">http://www.sqlmaestro.com/products/mysql/phpgenerator/</td></tr></table>
</body>
</html>
 
<?php function select()
  {
  global $a;
  global $showrecs;
  global $page;
 
  $res = sql_select();
  $count = sql_getrecordcount();
  if ($count % $showrecs != 0) {
    $pagecount = intval($count / $showrecs) + 1;
  }
  else {
    $pagecount = intval($count / $showrecs);
  }
  $startrec = $showrecs * ($page - 1);
  if ($startrec < $count) {mysql_data_seek($res, $startrec);}
  $reccount = min($showrecs * $page, $count);
?>
<table class="bd" border="0" cellspacing="1" cellpadding="4">
<tr><td>Table: test</td></tr>
<tr><td>Records shown <?php echo $startrec + 1 ?> - <?php echo $reccount ?> of <?php echo $count ?></td></tr>
</table>
<hr size="1" noshade>
<?php showpagenav($page, $pagecount); ?>
<br>
<table class="tbl" border="0" cellspacing="1" cellpadding="5"width="100%">
<tr>
<td class="hr">&nbsp;</td>
<td class="hr"><?php echo "ID" ?></td>
</tr>
<?php
  for ($i = $startrec; $i < $reccount; $i++)
  {
    $row = mysql_fetch_assoc($res);
    $style = "dr";
    if ($i % 2 != 0) {
      $style = "sr";
    }
?>
<tr>
<td class="<?php echo $style ?>"><a href="test.php?a=edit&recid=<?php echo $i ?>">Edit</a></td>
<td class="<?php echo $style ?>"><?php echo htmlspecialchars($row["ID"]) ?></td>
</tr>
<?php
  }
  mysql_free_result($res);
?>
</table>
<br>
<?php showpagenav($page, $pagecount); ?>
<?php } ?>
 
<?php function showroweditor($row, $iseditmode)
  {
  global $conn;
?>
<table class="tbl" border="0" cellspacing="1" cellpadding="5"width="50%">
<tr>
<td class="hr"><?php echo htmlspecialchars("ID")."&nbsp;" ?></td>
<td class="dr"><input type="text" name="ID" value="<?php echo str_replace('"', '&quot;', trim($row["ID"])) ?>"></td>
</tr>
</table>
<?php } ?>
 
<?php function showpagenav($page, $pagecount)
{
?>
<table class="bd" border="0" cellspacing="1" cellpadding="4">
<tr>
<?php if ($page > 1) { ?>
<td><a href="test.php?page=<?php echo $page - 1 ?>">&lt;&lt;&nbsp;Prev</a>&nbsp;</td>
<?php } ?>
<?php
  global $pagerange;
 
  if ($pagecount > 1) {
 
  if ($pagecount % $pagerange != 0) {
    $rangecount = intval($pagecount / $pagerange) + 1;
  }
  else {
    $rangecount = intval($pagecount / $pagerange);
  }
  for ($i = 1; $i < $rangecount + 1; $i++) {
    $startpage = (($i - 1) * $pagerange) + 1;
    $count = min($i * $pagerange, $pagecount);
 
    if ((($page >= $startpage) && ($page <= ($i * $pagerange)))) {
      for ($j = $startpage; $j < $count + 1; $j++) {
        if ($j == $page) {
?>
<td><b><?php echo $j ?></b></td>
<?php } else { ?>
<td><a href="test.php?page=<?php echo $j ?>"><?php echo $j ?></a></td>
<?php } } } else { ?>
<td><a href="test.php?page=<?php echo $startpage ?>"><?php echo $startpage ."..." .$count ?></a></td>
<?php } } } ?>
<?php if ($page < $pagecount) { ?>
<td>&nbsp;<a href="test.php?page=<?php echo $page + 1 ?>">Next&nbsp;&gt;&gt;</a>&nbsp;</td>
<?php } ?>
</tr>
</table>
<?php } ?>
 
<?php function showrecnav($a, $recid, $count)
{
?>
<table class="bd" border="0" cellspacing="1" cellpadding="4">
<tr>
<td><a href="test.php">Index Page</a></td>
<?php if ($recid > 0) { ?>
<td><a href="test.php?a=<?php echo $a ?>&recid=<?php echo $recid - 1 ?>">Prior Record</a></td>
<?php } if ($recid < $count - 1) { ?>
<td><a href="test.php?a=<?php echo $a ?>&recid=<?php echo $recid + 1 ?>">Next Record</a></td>
<?php } ?>
</tr>
</table>
<hr size="1" noshade>
<?php } ?>
 
<?php function editrec($recid)
{
  $res = sql_select();
  $count = sql_getrecordcount();
  mysql_data_seek($res, $recid);
  $row = mysql_fetch_assoc($res);
  showrecnav("edit", $recid, $count);
?>
<br>
<form enctype="multipart/form-data" action="test.php" method="post">
<input type="hidden" name="sql" value="update">
<input type="hidden" name="xID" value="<?php echo $row["ID"] ?>">
<?php showroweditor($row, true); ?>
<p><input type="submit" name="action" value="Post"></p>
</form>
<?php
  mysql_free_result($res);
} ?>
 
<?php function connect()
{
  $conn = mysql_connect("localhost", "user", "password");
  mysql_select_db("mydb");
  return $conn;
}
 
function sqlvalue($val, $quote)
{
  if ($quote)
    $tmp = sqlstr($val);
  else
    $tmp = $val;
  if ($tmp == "")
    $tmp = "NULL";
  elseif ($quote)
    $tmp = "'".$tmp."'";
  return $tmp;
}
 
function sqlstr($val)
{
  return str_replace("'", "''", $val);
}
 
function sql_select()
{
  global $conn;
  $sql = "SELECT ID FROM `test`";
  $res = mysql_query($sql, $conn) or die(mysql_error());
  return $res;
}
 
function sql_getrecordcount()
{
  global $conn;
  $sql = "SELECT COUNT(*) FROM `test`";
  $res = mysql_query($sql, $conn) or die(mysql_error());
  $row = mysql_fetch_assoc($res);
  reset($row);
  return current($row);
}
 
function sql_update()
{
  global $conn;
  global $_POST;
 
  $sql = "update `test` set ID=" .sqlvalue(@$_POST["ID"], false) ." where " .primarykeycondition();
  mysql_query($sql, $conn) or die(mysql_error());
}
function primarykeycondition()
{
  global $_POST;
  $pk = "";
  $pk .= "(ID";
  if (@$_POST["xID"] == "") {
    $pk .= " IS NULL";
  }else{
  $pk .= " = " .sqlvalue(@$_POST["xID"], false);
  };
  $pk .= ")";
  return $pk;
}
 ?>

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