Confirm before a form submit

[Sun Zaza]

Hi,

How can I get a confirmation before a form submit (ACP)?

I believe I have te edit this function:

function show_form_header($phpscript, $action = "", $name = "formular", $uploadform = 0) {
  global $site_sess;

  if ($uploadform) {
    $upload = " ENCTYPE=\"multipart/form-data\"";
  }
  else {
    $upload = "";
  }
  echo "<form action=\"".$site_sess->url(safe_htmlspecialchars(strip_tags($phpscript)))."\"".$upload." name=\"".$name."\" method=\"post\">\n";
  if ($action != "") {
    echo "<input type=\"hidden\" name=\"action\" value=\"".$action."\">\n";
  }
}

Thank you in advance,
Sun Zaza