PHP get value disappears - php

I have an html form that is filled with the values I get from a MySQL Database query. The query is by an id that is sent via GET.
I send the id to the form along with a button that is surrounded by an anchor <a>:
<a href='editRQS.php?id=$row[0]'><button class='edit'>Edit</button></a>
$row[0] is filled by the proper id and I'm sure it's working ok. When I click the button the url is sent carrying the id. It is then received at the other page like this:
<?php
$id = -1;
if(isset($_GET['id'])){
$id = $_GET['id'];
echo "<label class='exists' id='idRequest'> $id</label>";
}
if($id != -1 ){
echo '<form id="findRequest" class="hide" >';
} else {
echo '<form id="findRequest" class="show" >';
}
?>
The problem is that the id arrives at the page - but then it disappears. Any help will be greatly appreciated.
EDIT
The page seems to reload, i have no idea why, i have some javascript that manages some of the page functionality and the only thing that could cause this is an event handler for when the another form is submitted but I have prevented it like this:
$('anotherForm').on('submit',function(e){
.
.
.
e.preventDefault();
}
EDIT
Thanks to everybody that helped, i have yet to find the reason it doesn't work, i tried dissabling javascript and the page stoped reloading so i guess it's another thing that's messing my page up

The page is reloading because the form gets submitted. It isn't enough to preventDefault the form submission. Try e.preventDefault(); e.stopPropagation(); the latter preventing form submission when a submit button is clicked (clicks are still handled, and, in some cases propagate to the form, that is then submitted.
Also, I see you're using jQuery. Just let your event handler return false. jQuery automatically converts a false-returning handler to a e.preventDefault() ||e.returnValue = false e.stopPropagation() || e.cancelBubble = true; construction. Or you could write the code yourself...?

Check your register_globals setting, if it is on you will be overriding $_GET['id'] with the first statement.
You can easily check it by renaming $id to something other then $id.

Related

php : cannot see the hidden value submitted by Javascript

I'm pretty sure I'm missing something simple here, but it's driving me nuts !
This isn't the first form I'm using in PHP, but the first time submitting a hidden value.
When a menu item is clicked, I want to submit the page to itself - setting a simple parameter, so the php code does the processing.
The page gets submitted fine, but the hidden variable I set isn't available through _GET, _POST or _REQUEST. It should be _GET since that is what I've set as the method.
Here is the code if anyone can spot where I'm going wrong..
paramCustom is the one that I'm trying to set and work on.
The menu is a series of DIVs & anchors :
Option Xyz
The activateMenu javascript function is :
function activateMenu(optionTaken)
{
// Set the hidden variable
document.getElementById('paramCustom').value = optionTaken;
// Display it to confirm it is set correctly
var tt = document.getElementById('paramCustom').value;
console.log("paramCustom set to : " + tt);
// Submit the form
document.getElementById('linkSubmit').submit();
return false;
}
The form is coded this way :
<form method="get" action="showProducts.php" id="linkSubmit">
<input type="hidden" id="paramCustom" name="paramCustom" />
<input type="submit" tabindex="-1" style="display:none;" />
</form>
In the php of the same page I'm trying to spit them out but all of them show blank !!
echo "paramCustom get is : ".$_GET['paramCustom']."<br/>"; // This should work
echo "paramCustom request is : ".$_REQUEST['paramCustom']."<br/>";
echo "paramCustom post is : ".$_POST['paramCustom']."<br/>";
OK, problem is that you are not actually stopping the event from firing. So clicking on the link, the function gets called, form submitted but you are not actually stopping the event in the onclick. So form submits but is immediately redirected to the href of the link cancelling the form submit. When the href is blank, it defaults back to the page you are currently on.
The way you are adding the onclick to the link (using an inline attribute) is like wrapping the event in a closure. So when onclick fires, what is really fired is more like function(){ activateMenu('option-xyz'); }. Your call to activateMenu is returning false, but the closure around it is not. You can just add return in front of activateMenu to have the event itself return false and cancel. Change the link like so:
Option Xyz
And then the actual event itself will return false, not just the function.
Here is a simple example to illustrate what is happening.
Doing a little change to the HTML you can set the inline event via Javascript, which is a way better:
<a id="xyz" href="#">Option Xyz</a>
And this is the Javascript edited for your purpose:
function activateMenu(optionTaken)
{
var paramCustom = document.getElementById('paramCustom');
// Set the hidden variable
paramCustom.value = optionTaken;
// Display it to confirm it is set correctly
var tt = paramCustom.value;
console.log("paramCustom set to : " + tt);
// Submit the form
document.getElementById('linkSubmit').submit();
return false;
}
window.onload = (function() {
document.getElementById('xyz').onclick = function() {
activateMenu('option-xyz');
};
});
In PHP, as you know, $_GET gets the parameters of query string, $_POST of the POST data and $_REQUEST is a concat of the two arrays. In this case your method is GET so the value can be retrieved via _GET and _REQUEST, _POST is not going to work. Your code didn't worked to me probably because you had your function defined before DOM was loaded, so the event, when fired, probably throwed an exception.
This doesn't work because you haven't assigned a value. PHP won't recognize a field with a null value.
<input type="hidden" id="paramCustom" name="paramCustom" value="somevaluehere" />
[edit]
After testing this myself, it's because the onclick event is not behaving the way you anticipate. The easiest way to fix this is to use a HREF for you link. It's actually bad practice to rely solely on the onclick event anyway.
Option Xyz
This works perfectly.
The proper way to write an onclick looks like this:
Option Xyz
This works as well.
I've been using JQuery lately and it might be worth a shot.
Download the latest JQuery script and just link it to your page.
function activateMenu(optionTaken)
{
// Set the hidden variable
$("#paramCustom").val() = optionTaken;
// Display it to confirm it is set correctly
var tt = $("#paramCustom").val();
console.log("paramCustom set to : " + tt);
// Submit the form
document.getElementById('linkSubmit').submit();
return false;
}
This isn't that much different than what you had but maybe JQuery will do a better job of assigning the value to your hidden field...
Cheers,
K

jquery toggle between forms

I have ran out of ideas for this assignment for a class. I had to create two PHP forms using PHP_SELF and I am suppose to use javascript or jquery to toggle between the forms. I tried using
Form 1
Form 2
This does work on changing the forms, however when I hit the submit button the form it goes back to form 1 and doesn't display the results. The thing I have to figure out is after the form has been submitted using PHP_SELF, how to get it to stay on that form to show the results generated by the server.
You'll need to use something like this
if($_POST){
//display success message here
}else{
//display form here
}
You could add a hidden field to the form called formId and have PHP echo it back, so that you know from Javascript which form's results you're reading:
<?php
...
if (isset($_POST['formId']))
{
$show = 'form1' == $_POST['formId'] ? 'form1' : 'form2';
$hide = 'form1' == $_POST['formId'] ? 'form2' : 'form1';
// This PHP must be inside the Javascript section of the page, at end.
print <<<SETVISIBILITY
\$('#$show').style.display = 'block'; // Should be unnecessary (?)
\$('#$hide').style.display = 'hidden';
SETVISIBILITY;
}
?>
Or you can do the SUBMIT and result display all in jQuery, so that you needn't reload the page losing your form visibilities.

returning from a form submit call to a .php file

I have a questionnaire in a form. In the end of it the submit button is pressed that is supposed to call a .php file that inserts data into a database through its action information and afterwards show the last page that contains something like "thank you for participating etc." via the onsubmit info.
problem is that the last page is shown before the .php file is shown which means it is visible only for like half a second and then the php script is carried out which ends up showing a blank page.
The php script works it inserts data into the questionnaire correctly so there should be no mistakes syntax-wise.
any ideas if I have to exit the cript or something and return to the .html file or what could be wrong?
on your opening form tag add action="submit.php"
then once it goes to that page when the submit button is hit add this to the bottom of that php page:
header("Location: successfull.html");
IT sounds like what youre doing is showing the message with Javascript via the onsubmit event - this happens before the request is even set to the server and the php script. Youd either need to do an ajax form submission and then display the message when the request completes or make the php script redirect to the success message page when it is done.
But this is all just speculation without seeing any code... you should post some :-)
Why not submit the form to process.php then process it:
if(isset($_POST)){
$name = $_POST['name'];
// etc etc
// if all error checks pass, then echo out - thanks for taking part in our survey!
}
What you're doing is submitting it, and it seems you're getting javascript to say 'thank you' but it is being submitted before this thank you message can be displayed - no harm in echoing this out on your .php page!!
Update
You mention about redirecting to a page afterwards, but this can be done by:
header("Location: where/to/go.php");
exit;
But you can't do this with the above (echoing out a success) since it will redirect straight away.
The way I deal with this is putting the html contents into the php file.
<?php
if (!isset($_POST["submit"])) { // if page is not submitted to itself echo the form
?>
<html>
<head>
<title>survey</title>
</head>
<body>
<form method="post" action="<?php echo $PHP_SELF;?>">
...... (your form) ......
<input type="submit" value="submit" name="submit"><br />
</form><br />
</body>
</html>
<?
}
else {
$db = new PDO('...');
$db->exec(...);
echo "Thank you!";
}
?>
A few ways you could accomplish that.
You could make the php file it submits send out the data for the "thank you for participating" page (if you're fine with simply going to another page).
Alternatively, if you want to stay on the same page but just show the "thank you" notification, I would use JavaScript to disable the default action (e.preventDefault(); in the event handler) for the "submit" button on the forum, then also use JavaScript to use AJAX to submit the data.
An example (using JQuery), which won't change your page and perform the submit in the background, and display the "thank you" when done, on the current page.
$("a#confirmSubmit").click(function(e) {
e.preventDefault(); // Prevents the submit button from changing pages
data = {
Name: $("input#Name").attr("value")
// Add other data here also
};
$.post("/page/to/submit/to.php", data, function(d) {
//Write the code here to show the "thank you" notification.
//It will show upon completion here.
});
});
If you want to check for errors with inserting into the DB, you could check the value of the data of the AJAX call, to conditionally show the error. You can then return the user to the exact same form they were already on, with all the data still there, and show them an error message.

Disabling submit button stops form from being submitted PHP / Javascript

I think I got a classic problem but I was not able to find a working solution so far.
I have got a form , the user clicks "Send" and everything works fine using a PRG pattern and doing both client-side and server-side validation.
The problem arises when any user (let's assume he entered valid inputs) clicks more then once quickly before the server script ends its execution...
I do not get any duplicated entry because I took care of that but the browser does not go to my "thanks for submitting page".
Instead it re-submits the same page with the same values and what I get are the custom errors I set to warn the user he is trying to enter details already stored in the database. The details sent in the first place are all in the database but the user has no chance to know that.
I tried to disable the submit button on a submit event using jQuery but in that case the data are not submitted.
HTML
<div id="send-button-container">
<input id="send-emails" type="submit" name="send_emails" value="Send"/>
</div>
jQuery
$(document).ready(function(){
$('#mail-form').submit(function(){
$('#send-emails').attr('disabled','disabled');
});
});
I am wondering if I can force a submission using Javascript after disabling the button and also how to deal with UAs with Javascript disabled
Thanks in advance
Depending on server-side language, the submit button being disabled could cause problems. This is because disabled elements are not POSTed to the server. Languages like ASP.NET require the button value to be submitted so it knows what event handler to fire. What I usually do is hide the submit button, and insert a disabled dummy button after it, which appears identical to the user. Then in your onsubmit handler, you can return false and submit the form programmatically...
$('#mail-form').submit(function(){
var btn = $('#send-emails');
var disBtn = $("<input type='button'/>").val(btn.val()).attr("disabled", "disabled");
btn.hide().after(disBtn);
this.submit();
return false;
});
Contradictory to the other up-voted answers, please note that you do not need to explicitly return true from your submit handler for natural form submission: http://jsfiddle.net/XcS5L/3/
I assume this means you are depending on the value of the submit button to service the request? That is you are checking
$_REQUEST['send_emails'] == 'Send';
This is not good practice. You should never depend on the value of the submit button because that is the just what is displayed to the user. Instead, you should add a hidden input that contains the event you want to fire. After the form is submitted, you don't need to care what the value of the submit button is and you can disable it. All other non-disabled data in the form is still submitted.
You can indeed force the submission after disabling the button.
$(function () {
$("#mail-form").submit(function () {
$("#send-emails").attr('disabled', 'disabled');
window.location = '?' + $("#mail-form").serialize() + '&send_mails=Send';
return false;
});
});
Server side set a $_SESSION variable that keeps track of the last time they made a submission and block submissions within a certain time.
<?php
session_start();
if (isset($_REQUEST['send_emails'])) {
if (isset($_SESSION['mail_sent'])
&& strtotime($_SESSION['mail_sent']) < strtotime('5 seconds ago')
) {
redirect_to_thanks();
}
do_post();
}
function do_post() {
if (do_validate()) {
$_SESSION['mail_sent'] = time();
redirect_to_thanks();
}
else {
yell_at_user_a_lot();
}
}
?>
You have to return true; You could try this if u want a simple button to submit the form.
$(function(){
$('#submitID').one('click',function(){
$('#formTobeSubmitted').submit();
$(this).attr('disabled','disabled');
})
});
On server side, generate a random number into each form, store the number when the form is submitted, and discard the submit if that number has already been stored earlier. When the user has disabled javascript, this is the best you can do. (Concurrency issues can be tricky as the two identical requests are handled at the same time - make sure you use some sort of locking mechanism, such as a table with a unique field or the flock() command in PHP.)
On browser side, just set a flag when the form is submitted, and discard all later submits:
$('#mail-form').submit(function() {
if ($(this).data('submitted') {
return false;
} else {
$(this).data('submitted', true).addClass('submitted');
}
});
You can use the submitted class to make the buttons gray or something. This has a few advantages to simply disabling them; Josh already said one. Another is that Firefox likes to remember disabled states when you hit refresh, which can cause your users getting stuck in certain situations.

PHP/Javascript: Restart Form Button Isn't Working, Code Insde

Basically I want a confirmation box to pop up when they click the button asking if they sure they want to restart, if yes, then it destroys session and takes them to the first page. Heres what i got...
echo "<form id=\"form\" name=\"form\" method=\"post\" action=\"nextpage.php\">\n";
echo " <input type=\"button\" name='restart' value='Restart' id='restart'
onclick='restartForm()' />";
and for the script...
<script type=\"text/javascript\">
<!--
function restartForm() {
var answer = confirm('Are you sure you want to start over?');
if (answer) {
form.action=\"firstpage.php\";
session_destroy();
form.submit();
} else
alert ('Restart Cancelled');
}
// --
</script>";
EDIT: Note that pressing the button brings up the confirm box, but if you click okay nothing happens sometimes. Sometimes if u click cancel it still submits the form (To the original action)
Unless your session_destroy() method in Javascript actually sends a request to the PHP script or something, it looks like you are trying to put PHP code in your javascript, which will not work.
You should try redirecting them to something like firstpage.php?reset=1 and inside the PHP script, you can check for the reset flag, then call session_destroy().
You should use
onclick='restartForm(); return false;'
to prevent the form from being sent.
Also, session_destroy() is not JS AFAIK...
EDIT: you should also remember that sessions are server-side, not client side, so if you want to manipulate them you cannot do it in JS. The only thing you can do is calling a PHP (e.g. via AJAX) that does something with the sessions.

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