I'm trying to change the value of a PHP session variable when the user clicks on a div element.
There are several div elements on the page and each will change the session variable to a different value.
At the moment I have the following code under the first div as a test but can't get it to change the variable's value.
<div class="workpiece" onclick="<?php $_SESSION['pageRef'] = 1; ?>">
I would greatly appreciate any help as I'm very new to this.
Thanks
You are putting server side code in client side script. You cannot do this, as server side code executes before it is sent to the browser. What you can do, is send an ajax request to a PHP script on click.
<script>
function sendajax() {
$.post('scriptforsession.php', {}, function(response) {
console.log(response);
});
}
</script>
onclick='sendajax();'
Ajax would be one solution but I think what you are trying could also be handled by simply putting the page reference in a GET. Though this will make the page reload. Then in your PHP simple use the $_GET['pageRef']
<div class="workpiece" onclick="window.location='?pageRef=1';">
Related
I'm displaying data from DB like this:
<?php foreach ($r as $k => $v):?>
<div data-role="collapsible" data-mini="true" class="collapsible">
Name: <?=$v['name']?>
</div>
<?php endforeach; ?>
Now when I add new data to DB and the form is submitted, my script redirects back to this page. How do I show the new data immediately without manually refreshing the browser? I usually don't have this issue if I'm not using Jquery Mobile.
You could send the form with jquery ajax
$('form[name="myform"]').submit(function(evt){
evt.preventDefault();
$.post('/my_form_handler.php', $(this).serialize())
.done(function(data){
//Populate dom elements here with new data
}).fail(function(data){
//Handle failed ajax post.
});
});
And then on successful post change the content of the dom-elements.
Not 100% sure i got the right syntax for it but i think it should give you a general idea on how to do it.
The problem here is that the data is hard coded into the page's HTML. After your form submission it's jQueryMobile that's changing the page/view, and no refresh of the page takes place so you're still seeing the same data.
You should refactor to create the loop with JSON data (loaded via AJAX). If the data is cached in a local variable, you can either add to it with the form's data, or make a fresh AJAX call to the server (recommended if you need sorting or filtering).
After reloading the data, the rendering code can be called, showing the new list.
it is easy.
you can send the request to the server using ajax.
and on the server side, you have to make the function to return the data added.
the ajax function will get the success or fail function.
the success function will run if it works.
on the success function , you have to add the content using javascript jquery with the returned data.
Thanks
I have a one page website in the works that has a contact form where its contact error and contact thank you messages are placed further down the page as hidden divs.
The contact form calls an external php file that calls the anchor links of the error and thank you message divs in the index.html file.
www.photograsurfer.com/test/index.html
www.photograsurfer.com/test/code/contact-panel.php
Everything works successfully as long as the divs are not hidden. So now I need to use the following javascript to get the hidden divs to display when needed.
<script type="text/javascript">
function showContactPanelError() {
document.getElementById('contact-panel-error').style.display = "block";
}
</script>
My problem, besides being a complete PHP beginner, is that I don't know how to get the PHP file to reference the Javascript code to display the hidden divs properly on the main page.
Any help is appreciated.
Thanks.
Use jQuery forms (http://malsup.com/jquery/form/) to submit your form via AJAX, then show/hide divs depending on values you return from PHP scripts.
you could assign php variable to javascript as
var error="<?php echo $_GET['error']; ?>";
the $error is the data passed along with the url like wwww.example.com/test.php?error=1
Now you could check var error and call your function showContactPanelError().
I ended up going with a mixture of the 2 methods on these pages.
http://trevordavis.net/blog/ajax-forms-with-jquery
https://spruce.it/noise/simple-ajax-contact-form/#contact
Ditched the div idea since the Ajax method allowed me to not reload the page and enter error and thank you messages within the contact form itself. Seemed like an easier approach.
Thanks for all of the suggestions, as I never would have looked at using Ajax otherwise.
You can add a onclick event on submit button. On clicking it will create an ajax call send data to the required external PHP file and then on success will display the hidden division properly on the main page.
here's a sample code just for an explanation
**
* Description : Function that will trigger the AJAX request.
* #param none
*/
function CategorySubscriber_Unsubscribe(){
var data = {
'data-1': data-1,
'data-2': data-2,
// as per your need you can put any number of data
};
var url = // your url
jQuery.post(url, data, function(response){
jQuery.show("#your-div-id");
});
}
function(response) will be executed when ajax call will be in success status.
You can learn it from these links
http://www.w3schools.com/jquery/ajax_post.asp
http://api.jquery.com/jQuery.post/
I have a PHP Function that I would like to integrate into my (existing) web page. Further, I would like it to execute when the user clicks a link on the page. The function needs to accept the text of the link as an input argument.
Everything I've researched for sending data to a PHP script seems to involve using forms to obtain user input. The page needs to accept no user input, just send the link-text to the function and execute that function.
So I guess the question is two-part. First, how to execute a PHP script on link click. And second, how to pass page information to this function without the use of forms. I am open to the use of other technologies such as AJAX or JavaScript if necessary.
EDIT:: Specifically what I am trying to do. I have an HTML output representing documentation of some source code. On this output is a series of links (referring to code constructs in the source code) that, upon being clicked, will call some python function installed on the web server (which leads me to think it needs called via PHP). The python function, however, needs the name present on the link as an input argument.
Is there some sort of interaction I could achieve by having JavaScript gather the input and call the PHP function?
Sorry for the vagueness, I am INCREDIBLY new to web development. If anything is unclear let me know.
You'll need to have a JS function which is triggered by an onclick event which then sends an AJAX request and returns false (so it won't be redirected to a new page in the browser). You can do the following in jQuery:
jQuery:
<script type="text/javascript" src="jquery.min.js"></script>
<script type="text/javascript">
function doSomething() {
$.get("myfile.php");
return false;
}
</script>
And in your page body:
Click Me!
In myfile.php:
You can add whatever function you want to execute when the visitor clicks the link. Example:
<?php
echo "Hey, this is some text!";
?>
That's a basic example. I hope this helps.
You will need to use AJAX to accomplish this without leaving the page. Here is an example using jQuery and AJAX (this assumes you have already included the jQuery library):
First File:
<script language="javascript">
$(function(){
$('#mylink').click(function(){
$.get('/ajax/someurl', {linkText: $(this).text()}, function(resp){
// handle response here
}, 'json');
});
});
</script>
This text will be passed along
PHP File:
$text = $_REQUEST['linkText'];
// do something with $text here
If you are familiar with jQuery, you could do the following, if you don't want the site to redirect but execute your function:
in your html head:
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
the link:
Execute function
in ajax.php you put in your function to be executed.
Maybe something like this:
....
<script>
function sendText(e)
{
$.ajax({
url: '/your/url/',
data: {text: $(e).html()},
type: 'POST'
});
}
</script>
You can use query strings for this. For example if you link to this page:
example.php?text=hello
(Instead of putting a direct link, you can also send a ajax GET request to that URL)
Inside example.php, you can get the value 'hello' like this:
<?php
$text = $_GET['hello'];
Then call your function:
myfunction($text);
Please make sure you sanitize and validate the value before passing it to the function. Depending on what you're doing inside that function, the outcome could be fatal!
This links might help:
http://net.tutsplus.com/tutorials/php/sanitize-and-validate-data-with-php-filters/
http://phpmaster.com/input-validation-using-filter-functions/
Here's an overly simplistic example of what you're trying to do..
Your link:
Some Action
Your PHP file:
<?php
if (isset($_GET['action']))
{
// make sure to validate your input here!
some_function($_GET['action']);
}
PHP is a server side language i.e. it doesn't run in the web browser.
If you want a function in the browser to operate on clicking a link you are probably talking about doing some Javascript.
You can use the Javascript to find the text value contained in the link node and send that to the server, then have your PHP script process it.
On my page I have a search result that contains a list with users where each is followed by an "addfriend" button. Each row contains a username and userID. Meanwhile the ID of the user that requested the searchresult is stored in a Session variable.
When the addfriend-botton is clicked the following 2 things should happen:
Store the userID and $_SESSION['userID'] is a MySQL table which describes the relationship.
Do NOT refresh the page (this the core of my problem) but stay focussed and change the state of the button to e.g. "friend request send". I'm thinking of GetElementByID().style method.
I was thinking of this:
<a href="#" onClick="addFriend('<? echo $_SESSION['userID'];?>','<? echo $rij['userID']; ?>')">
which calls the javascript function addfriend
I was hoping to catch the two ID's like this:
<script>
function addfriend(id1, id2)
{
//server side php code where I use value of
//the client-side javascript variables: +id1+ and +id2+ .
}
</script>
Is this at all possible or I'm I thinking the wrong way? Any suggetions on how to accomplish this?
You are in the right way, inside your addFriend() function, you can call one php file (via AJAX) and send the IDS without refresh the page. I think better you work with Jquery in this case, something like this:
<script>
function addfriend(id1, id2)
{
$.ajax({
type: 'POST',
url: 'yourPHPfile.php',
data: { your_id_1:id1, your_id_2:id2 },
success: function(data){
if(data){
alert('Done!');
}
},
dataType: 'text'
});
}
</script>
And in your PHP File you can do this:
<?php
//receive Ids
$id1 = $_POST['your_id_1'];
$id2 = $_POST['your_id_2'];
//do something here
echo "OK!";
<?
to do this work you need download and add the jQuery plugin in your page, rather into head tag
<head>
<script type="text/javascript" src="jquery.js"></script>
</head>
Good work and don't give up! (:
You can do this using AJAX (asynchronous JavaScript and XML), which is really just a fancy term for "sending stuff to a server with JavaScript and getting a response back, without reloading the page". There's nothing special about AJAX; it just involves using plain old JavaScript to send an HTTP request.
Check out jQuery, a JavaScript library that handles most of the technical stuff for you. Specifically, look at its post() function, which allows you to send data to a PHP script using the $_POST system variable. There are lots of clear examples on that page.
Note that you don't need jQuery to use AJAX; jQuery is just a library that makes things easier. If you really want to learn how the JavaScript side of AJAX works, try following one of the many tutorials out there, such as Mozilla's or this one.
AJAX is the answer you're looking for.
It sounds like you already have a basic understanding of this, but to clarify, Javascript executes on the client side, and PHP executes on the server side. So you would have to make a call back to your server in order to interact with PHP/MySQL.
The purpose of AJAX is to do this without requiring a page refresh.
This question may seem completely stupid, but say i have a PHP page with some form processing at the top in php and a html form underneath with the action of submitting to same page and method of post. How do i get the result via ajax, ie. send form to self without refreshing the page, if that makes sense? Thanks
It sounds like you're asking about Ajax basics, right? I suggest using jQuery to handle the Ajax part.
Put jQuery in your page, and then do something like
$(document).ready(function(){
$('#submit_button').click(function(){
var something='value to send to PHP';
$.post('name_of_page.php',{"a_var":something},function(data){ /* do something with the data you received back*/ },'json');
});
});
Then in your PHP page, set up to handle a post or normal HTML output.
<?php
if($_POST['a_var']){
$result=do_something($_POST['a_var']);
echo json_encode($result);
exit;
}
//if there was no POST value, it continues to here
<html>
This is the rest of your page.
You'd have the form and the above javascript and so on here.
</html>
In your page, check if the page has POST parameters. If it does, process them and return a confirmation. If it doesn't, display the form.