Checkbox always returning true in javascript/php

Question

I'm trying to get the value of the checkbox using an Ajax/Javascript response which passes the value to PHP so i can perform a query based on the value ("Checked","Not checked")

<input type="checkbox" name="status" onclick="updateStatus(<? echo $data['id']; ?>,this.checked)">

The Javascript/Ajax code for the function "updateStatus" is as followed

function updateStatus(id,value) {
if (window.XMLHttpRequest) {
    http = new XMLHttpRequest()
} else if (window.ActiveXObject) {
    http = new ActiveXObject("Microsoft.XMLHTTP")
} else {
    alert("Your browser does not support XMLHTTP!")
}
http.abort();
http.open("GET", "../functions/ajax.php?check=update_status&id=" + id + "&checked="+value, true);
http.onreadystatechange = function () {
     if (http.readyState == 4) {
        alert(http.responseText);
     }
 }
 http.send(null)

The PHP function inside functions/ajax.php

if(isset($check) and $check == 'update_status' and isset($_GET['id'])){
    $id = mysql_real_escape_string($_GET['id']);
    $checked= mysql_real_escape_string($_GET['checked']);
if($checked == true) {
    echo "Checked";
} elseif($checked == false) {
    echo "Not checked";
} else {
    echo "Invalid response";
}

when using this code it always returned "Checked" any idea why ?

You were asked about exact value of it. Try var_dump($_GET['checked']) to see it in response. — Viktor S.
– Viktor S., Commented Jan 11, 2013 at 17:02
Don't mysql_real_escape_string data until you are about to merge it into a string of SQL. For that matter, don't use it at all, it is from an obsolete database API and should use a modern replacement. — Quentin
– Quentin, Commented Jan 11, 2013 at 17:04

Quentin · Accepted Answer · 2013-01-11 17:02:53Z

5

In the JS. value will be true or false. When you stringify either of those, you will get a string ('true' or 'false').

Thus $_GET['checked'] will be either "true" or "false" both of which == true.

To fix this on the PHP side, compare to the string "true" and the string "false"; not the boolean.

answered Jan 11, 2013 at 17:02

Quentin

949k136 gold badges1.3k silver badges1.4k bronze badges

Sign up to request clarification or add additional context in comments.

Comments

blo0p3r · Accepted Answer · 2013-01-11 17:27:23Z

4

You are getting $_GET['checked'] as a String. Change to something like:

if($checked == "true") {
    echo "Checked";
} elseif($checked == "false") {
    echo "Not checked";
} else {
    echo "Invalid response";
}

edited Jan 11, 2013 at 17:27

blo0p3r

6,8588 gold badges51 silver badges70 bronze badges

answered Jan 11, 2013 at 17:04

nimlhug

1214 bronze badges

Comments

Community · Accepted Answer · 2017-05-23 12:12:34Z

0

This might help you in your answer https://stackoverflow.com/a/4228827/90648

You can try replacing the code

"&checked="+value

with

(value ? "&checked=true" : '')

This way you will only send the value true when it is checked, and not send anything (which you can check in PHP with isset)

or you can go with

(value ? "&checked=true" : '&checked=')

which will again, not send anything, thus empty string will be interpreted as false.

edited May 23, 2017 at 12:12

CommunityBot

11 silver badge

answered Jan 11, 2013 at 17:06

Azder

4,7287 gold badges39 silver badges57 bronze badges

Collectives™ on Stack Overflow

Checkbox always returning true in javascript/php

3 Answers 3

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related