checkbox question with php

My question is when user click on checkbox, then user is activated. this code is working fine. But when user ag开发者_如何学编程ain click on uncheckbox, then again user de-activated. How to do that? here is my working code.

Activate user when user click on checkbox

if($_GET['doAction'] == 'Activate') {
    if(!empty($_GET['q'])) {
        $userid = $_GET['q'];
        $conn = db_connection();
        $query = "UPDATE user SET activate = '1' WHERE userid = '".$userid."' ";
        $result=$conn->query($query);
    }
}

here is my checkbox

<input type="checkbox" name="app" onchange="callUser(this.value,doAction.value);" value="<?php echo $userid;?>" <?php if($row['approved'] == '1'){ echo "checked=\"true\""; }?>/>
<input type="hidden" name="doAction" id="doAction" value="Approved" />

thanks you so much. :-) EDIT-> Here is calluser() Function

<script type="text/javascript">
function callUser(str,action,third)
{
 var xmlhttp;    
if (str=="")
{
document.getElementById("txtHint").innerHTML="";
return;
}
if (window.XMLHttpRequest)
  {// code for IE7+, Firefox, Chrome, Opera, Safari 
  xmlhttp=new XMLHttpRequest();
}
else
 {// code for IE6, IE5
 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
 }
xmlhttp.onreadystatechange=function()
 {
if (xmlhttp.readyState==4 && xmlhttp.status==200)
 {
 document.getElementById("txtHint").innerHTML=xmlhttp.responseText;

}
}
xmlhttp.open("GET","adminPanel.php?    q="+str+"&doAction="+action+"&app="+third,true);
    xmlhttp.send();
}
 </script>

Here is screenshot http://i.stack.imgur.com/MpQfC.png

---

You should send the state of the checkbox rather than the hidden field value.

onchange="callUser(<?php echo $userid;?>,this.value);"

then on the PHP side you can do a

$userid = $_GET['q'];
if(!empty($_GET['doAction']) {
   ... activate ...
}
else { ... deactivate ... }

Also, please be aware that your code sample and my anwser are both EXTREMELY insecure. You are wide open to SQL injection attacks and potential permission problems.

EDIT : fix not sending user ID.

---

Update: Seeing as how the just revealed Javascript method kind of ruins the default form sending abilities of a web page, please ignore this answer.

An unchecked checkbox does not get passed back to the server when the form is submitted. So, in this case:

if($_GET['doAction'] == 'Activate') {
    if(!empty($_GET['q'])) {
        $userid = $_GET['q'];
        $conn = db_connection();

        if (!empty($_GET['app'])) {
            $query = "UPDATE user SET activate = '1' WHERE userid = '".$userid."' ";
        }
        else {
            $query = "UPDATE user SET activate = '0' WHERE userid = '".$userid."' ";
        }
        $result=$conn->query($query);
    }
}

Hope this helps

Also, you would do well to be using parameters and binding the variables to the SQL rather than concatenating strings. This will go a long way to preventing SQL injection attacks.

---

Your need if user uncheck checkbox than doAction='Deactivate'?
Post here source code of callUser function

---

one other thing is you dont use value to set if its checked or not,

checked="checked" means enabled in the Input Tag

Then who ever said it is not sent is correct your best way of detecting them is using a isset($_REQUEST['checkBx'])

E.G

if(isset($_REQUEST['checkbx'])){
  // code for they are enabled
}else{
  // code for they are disabled
}