I know it is not possible to simply call a function through ajax. As it only sends data via HTTP headers. However, I am trying to achieve something. I'm trying to execute a piece of PHP code, by the click of a button. The code consists of a shell_exec("omxplayer file.mp3")
So my ultimate goal is, to have a page load, display a button, which in turn, once clicked, will execute this piece of code (shell command).
I have looked for solutions and have not found one, even though there have been a lot of questions asked with a similar title to mine.
How can I achieve this concept?
EDIT: My ultimate goal is to use the shell_exec() to start playing a file using omxplayer on a linux machine.
You can use .get()
<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
<script>
$(document).ready(function() {
$("button").click(function() {
$.get("script.php?code=myFunction", function(data, status) {
alert("Data: " + data + "\nStatus: " + status);
});
});
});
</script>
</head>
<body>
<button>Execute Command</button>
</body>
</html>
script.php
if (!empty($_GET['code']) {
$output = shell_exec(<do shell command here>):
echo $output;
}
The following assumes that xxx is your PHP file and output is the response from the xxx file:
button.onclick = function() {
$.ajax({
url: '/my/site/xxx.php',
data: {action: 'test'},
type: 'post',
success: function(output) {
alert(output);
}
});
};
You are looking at things the wrong way.
Create a separate page that executes the exec command and displays the result.
Create an interface page where - and you have a wide choice of options - when the user clicks a button you send him to the exec page.
I'm assuming you need or want to feed data to the exec command.
The page with the exec command can process values sent using GET and more securely POST (or REQUEST)
Just like any other html form would.
If you want to create a somewhat modern feel to an old school browser bash implementation you have a few options.
Submit onto self. Every time you submit the page will be redrawn
with the new data and the new exec will have run.
Submit into a target iframe. The interface will linger, the
iframe will update the contents.
xhtmlhttp post (asynchronous or "ajax" even though it doesn't
have to be) and update the contents of a div with the response -
from a separate php page.
Related
Is it possible to use Ajax, Jquery or Javascript to call a specific PHP Function and refresh / reload it every 10 seconds for example inside a specific Div or areas?
Connection.php
function TerminalStatus ($IPAddress, $portStatus ) // Responsible for current terminal status
{
$connectStatus = fsockopen($IPAddress, $portStatus, $errno, $errstr, 10); // Build cconnection to Terminal socket 25001
if (!$connectStatus) {
echo "$errstr ($errno)<br />\n";
} else {
$Status = fgets($connectStatus) ;
echo $Status ();
}
}
This connection is just to see the current status of a terminal.
I want to see the status of this function at the bottom of my index.php without refreshing the whole page.
I can accomplish this by putting this function in its own PHP Files (status.php) and using Javascript in the following way:
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.0/jquery.min.js"></script>
<script type="text/javascript">
var auto_refresh = setInterval(
function ()
{
$('#Status').load('status.php');
}, 1000); // refresh every 1000 milliseconds
</script>
But i just want to utilise the function instead.
Is this possible?
The solution you have already is the correct way to do this: the JavaScript fetches a URL, and that URL renders the appropriate piece of content.
It's important to remember that, as far as the web browser is concerned, PHP doesn't exist. Any request from the browser - whether you've typed in a URL, followed a link, submitted a form, made an AJAX request, etc - is just a message to some remote server for a particular URL, perhaps along with some extra headers and body data. When the server receives that request, it can do whatever it likes to generate a response to the browser.
So when you write $('#Status').load('status.php');, the browser is sending a request to the server, which happens to be configured to execute the PHP script status.php. You can then do what you like in PHP to produce the response - but there is no direct link between a request and a PHP function.
However, as others have pointed out, you don't have to create a new PHP file for every piece of behaviour you want, because inside the PHP code you can check things like:
the query string parameters, in $_GET
submitted form data, in $_POST
the HTTP headers from the request
These can be set by your JavaScript code to whatever you like, so you could for instance write $('#Status').load('index.php?view=statusonly'); and then at the top of index.php have code like this:
if ( $_GET['view'] === 'statusonly'] ) {
echo get_status();
exit;
}
How you arrange this is entirely up to you, and that's what programming is all about 🙂
That's impossible to do this operation just with the PHP function.
you should use javascript as you use that or use socket in javascript to connect you status.php and update without refresh the whole page.
I'm not sure if i understood the problem but you can use AJAX to execute specific function. Something like this:
First build your ajax:
$.ajax({
type: "POST",
url: "URL_TO_PHP_FILE",
data: "refreshStatus", // this will call the function
success: function(status){
$('#Status').text(status); // this will load the info you echo
},
});
Since you want to do it every second - wrap the whole thing with interval (i use your code from the question):
var auto_refresh = setInterval( function () {
$.ajax({
type: "POST",
url: "URL_TO_PHP_FILE",
data: "refreshStatus",
success: function(status){
$('#Status').text(status);
},
});
}, 1000);
Then, on you PHP_FILE add condition the execute the specific function when POST been done:
if ($_SERVER["REQUEST_METHOD"] == "POST" && $_POST['refreshStatus']) {
// run this code
}
Is that what you aimed to achieve?
jQuery::load() supports fragment identifiers. So you can just load the part that you want to replace:
$( "#Status" ).load( "status.php #PartId" );
This will load the HTML output of the script and extract the part. The PHP script will run completely - the rest of the HTML output will be thrown away on the JS side.
I've started working with ajax a little lately, but I'm having trouble with something I feel is incredibly simple: storing a JS variable in PHP.
Say I want to store a zip code (assigned with Javascript) and pass that to a PHP variable via AJAX: Why doesn't this work?
Keeping it simple for demonstration purposes, but this is the functionality I desire..
zipCode.js:
$(document).ready(function() {
var zip = '123456';
$.ajax({
url: 'zip.php',
data: {zip_code:zip},
type: 'POST'
});
});
zip.php:
<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
<script src="zipcode.js"></script>
</head>
<body>
<?php
echo $_POST['zip_code'];
?>
</body>
</html>
An error: "Notice: Undefined index: zip_code" is all that is returned. Shouldn't "123456" be echo'd out?
You are supposed to put this:
<?php
// query database before echoing an associative array of `json_encode()`ed data if a response is needed
echo json_encode(array('zip_code' => $_POST['zip_code']);
?>
on a separate page, that is not an HTML page. AJAX just sends to that page, so you can use it and echo it out, making database queries before that, or what have you. Upon success you will see the result of your echo as the argument passed to the success method in this case if you used data as the argument the result for zip_code would be held in data.zip_code. Also, set your dataType:'JSON' in $.ajax({/*here*/}).
Here:
var zip = '123456';
$.ajax({
url: 'zip.php',
data: {zip_code:zip},
type: 'POST',
dataType: 'JSON',
success: function(data){
// in here is where you do stuff to your page
console.log(data.zip_code);
}
});
When you load the page, a call is being made to the server for zip.php, however that request is in no way linked to the page you're currently viewing.
If you look at the response to your ajax request - you'll see a copy of the page with the correct zip code echo'd
The actual answer then depends on what exactly you're trying to do (and a less simplified version of the code) to give you the best option.
The current setup you have doesn't make sense in practice
That is not how AJAX works. Thake a look at the example below. It will make an AJAX post to handle_zip.php and alert the results (Received ZIP code 123456)
start_page.html:
<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
<script src="zipcode.js"></script>
</head>
<body>
This is just a static page.
</body>
</html>
zipcode.js:
$(document).ready(function() {
var zip = '123456';
$.ajax({
url: 'handle_post.php',
data: {zip_code:zip},
type: 'POST',
success: handleData
});
});
}
function handleData(data) {
alert(data);
}
handle_post.php:
<?php
die ('Received ZIP code ' . $_POST['zip_code']);
As others have mentioned, it sounds like you're expecting the two bits of code to run at the same time. The reality is that:
zip.php will be parsed on the server (and resulting in the error)
Server will then serve up the HTML to the browser (which will have a blank body due to the $_POST not existing when the PHP was parsed)
browser will see the javascript .ready() and run that code
server will handle the POST request to zip.php, and generate the HTML you're expecting. It'll be returned in the AJAX response, but as you're not handling the response, nothing is shown in the current session. (you can see the POST response using any of the common web developer tools)
Remember, PHP runs on the server, then any javascript runs on the client. You're also missing the step of handling the response from the request you made in your javascript.
try this to give you better idea of what's happening.
$.ajax({
url: 'zip.php',
data: {zip_code:zip},
type: 'POST'
});.done(function(data ) {
console.log(data)
});
In your code, the server is creating the page first, so no javascript is run yet, therefore it creates an error because $_POST['zip_code'] doesn't exist. Then it sends this page to your browser and you can see that. At this point is when your browser executes the javascript, it sends the request again, now with POST data, the server should return the response of the request and you should be able to see it in the console.
You could make this 2 separate pages, one for viewing the page, and anotherone for processing the ajax request, or if for your application you want to do it in the same page, you would need an if statement to get rid of that error, something like
if(isset($_POST['zip_code'])){
echo $_POST['zip_code];
}
before we start apologies for the wording and lack of understanding - I am completely new to this.
I am hoping to run a php script using Ajax - I don't need to send any data to the php script, I simply need it to run on button press, after the script is run I need to refresh the body of the page. What I have so far:
HMTL Button with on click:
<font color = "white">Next Question</font>
JS Ajax call:
function AjaxCall() {
$.ajax({
url:'increment.php',
type: 'php',
success:function(content,code)
{
alert(code);
$('body').html(content);
}
});
}
this runs the php script but doesn't stay on the current page or refresh the body - has anyone got any ideas - apologies if this is completely wrong I'm learning - slowly.
Many thanks in advance.
**As a small edit - I don't want a user to navigate away from the page during the process
How about using load instead of the typical ajax function?
function AjaxCall() {
$(body).load('increment.php');
}
Additionally, if you were to use the ajax function, php is not a valid type. The type option specifies whether you are using GET or POST to post the request.
As far as the dataType option (which is what I think you mean), The Ajax doesn't care what technology the called process is using (like ASP or PHP), it only care about the format of the returned data, so appropriate types are html, json, etc...
Read More: http://api.jquery.com/jquery.ajax/
Furthermore, if you are replacing the entire body content, why don't you just refresh the page?
your ajax should be
function AjaxCall() {
$.ajax({
url:'increment.php',
type: 'post',
success:function(data)
{
console.log(data);
$('body').html(data);
}
});
}
if you want to learn ajax then you should refer this link
and if you just want to load that page then you can use .load() method as "Dutchie432" described.
If you are going to fire a javascript event in this way there are two ways to go about it and keep it from actually trying to follow the link:
<font color = "white">Next Question</font>
Note the return false;. This stops the following of the link. The other method would be:
<font color = "white">Next Question</font>
Note how this actually modifies the href to be a javascript call.
You can study about js and ajax here http://www.w3schools.com/ajax/default.asp will help a lot. Of course all js functions if called from internal js script should be inside <script></script> and if called from external you call the js gile like <script src"somejs.js"></script> and inside js there is no need for <script> tags again. Now all those function do not work by simply declaring them. So this:
function sayHello(){
alert("Happy coding");
}
doesn't work because it is just declared and not called into action. So in jQuery that you use after we declare some functions as the sayHello above we use:
jQuery(document).ready(function($){
sayHello();
});
Doing this we say that when everything is fully loaded so our DOM has its final shape then let the games begin, make some DOM manipulations etc
Above also you don't specify the type of your call meaning POST or GET. Those verbs are the alpha and omega of http requests. Typically we use GET to bring data like in your case here and POST to send some data for storage to the server. A very common GET request is this:
$.ajax({
type : 'GET',
url : someURL,
data : mydata, //optional if you want to send sth to the server like a user's id and get only that specific user's info
success : function(data) {
console.log("Ajax rocks");
},
error: function(){
console.log("Ajax failed");
}
});
Try this;
<script type="text/javascript">
function AjaxCall() {
window.location.reload();
}
</script>
<body>
<font color = "white">Next Question</font>
</body>
I have a bookmarklet which a user adds to their own browser bookmarks toolbar which collects images from a page they are looking at.
I want to log each time a user is clicking on any site and store the data in a mysql table. So i'm using an ajax call to post to a php file which processes the data sent to it.
However, this sometimes works and sometimes does not. Meaning, it works on some sites and not others.
What I'm trying is this:
(function()
{ // declare variables e.g. div.ids, div content etc then display it
......
//log the click
var dataString = '&url=' + encodeURIComponent(window.location.href) + '&page_title=' + encodeURIComponent(document.title);
$.ajax({
type: "POST", // form method
url: "http://myurl.com/includes/log_clicks.php",// destination
data: dataString,
cache: false
});
//END log the click
})();
When it doesn't work and i use Firebug to find out why, i sometimes get the error: TypeError: $ is undefined $.ajax({
Sometimes it still posts to the php file but with no data
Is there a better way to call ajax from within a js file on a user's browser?
As per suggestions, I've tried loading jquery by simply amending one of the variables like so:
div.innerHTML = '<script src="http://code.jquery.com/jquery-latest.min.js" type="text/javascript"></script><div class=....';
But that made no difference
You need jQuery present on the page in order to perform this. You will need to load jQuery if not present. A great approach is outlined here using the jQuerify code which actually just loads a portion of jQuery functionality that is needed.
How can I fix the script below so that it will work EVERY TIME! Sometimes it works and sometimes it doesn't. Pro JQuery explains what causes this, but it doesn't talk about how to fix it. I am almost positive it has to do with the ajax ready state but I have no clue how to write it. The web shows about 99 different ways to write ajax and JQuery, its a bit overwhelming.
My goal is to create an HTML shell that can be filled with text from server based text files. For example: Let's say there is a text file on the server named AG and its contents is PF: PF-01, PF-02, PF-03, etc.. I want to pull this information and populate the HTML DOM before it is seen by the user. A was ##!#$*& golden with PHP, then found out my host has fopen() shut off. So here I am.
Thanks for you help.
JS - plantSeed.js
var pageExecute = {
fileContents:"Null",
pagePrefix:"Null",
slides:"Null",
init:function () {
$.ajax({
url: "./seeds/Ag.txt",
success: function (data){
pageExecute.fileContents = data;
}
});
}
};
HTML - HEAD
<script type="text/javascript">
pageExecute.init();
</script>
HTML - BODY
<script type="text/javascript"> alert(pageExecute.fileContents); </script>
Try this:
var pageExecute = {
fileContents:"Null",
pagePrefix:"Null",
slides:"Null",
init: function () {
$.ajax({
url: "./seeds/Ag.txt",
async: false,
success: function (data){
pageExecute.fileContents = data;
}
});
}
};
Try this:
HTML:
<div id="target"></div>
JavaScript:
$(function(){
$( "#target" ).load( "pathToYourFile" );
});
In my example, the div will be filled with the file contents. Take a look at jQuery .load() function.
The "pathToYourFile" cand be any resource that contains the data you want to be loaded. Take a look at the load method documentation for more information about how to use it.
Edit: Other examples to get the value to be manipulated
Using $.get() function:
$(function(){
$.get( "pathToYourFile", function( data ) {
var resourceContent = data; // can be a global variable too...
// process the content...
});
});
Using $.ajax() function:
$(function(){
$.ajax({
url: "pathToYourFile",
async: false, // asynchronous request? (synchronous requests are discouraged...)
cache: false, // with this, you can force the browser to not make cache of the retrieved data
dataType: "text", // jQuery will infer this, but you can set explicitly
success: function( data, textStatus, jqXHR ) {
var resourceContent = data; // can be a global variable too...
// process the content...
}
});
});
It is important to note that:
$(function(){
// code...
});
Is the same as:
$(document).ready(function(){
// code
});
And normally you need to use this syntax, since you would want that the DOM is ready to execute your JavaScript code.
Here's your issue:
You've got a script tag in the body, which is asking for the AJAX data.
Even if you were asking it to write the data to your shell, and not just spout it...
...that's your #1 issue.
Here's why:
AJAX is asynchronous.
Okay, we know that already, but what does that mean?
Well, it means that it's going to go to the server and ask for the file.
The server is going to go looking, and send it back. Then your computer is going to download the contents. When the contents are 100% downloaded, they'll be available to use.
...thing is...
Your program isn't waiting for that to happen.
It's telling the server to take its time, and in the meantime it's going to keep doing what it's doing, and it's not going to think about the contents again, until it gets a call from the server.
Well, browsers are really freakin' fast when it comes to rendering HTML.
Servers are really freakin' fast at serving static (plain-text/img/css/js) files, too.
So now you're in a race.
Which will happen first?
Will the server call back with the text, or will the browser hit the script tag that asks for the file contents?
Whichever one wins on that refresh is the one that will happen.
So how do you get around that?
Callbacks.
Callbacks are a different way of thinking.
In JavaScript, you perform a callback by giving the AJAX call a function to use, when the download is complete.
It'd be like calling somebody from a work-line, and saying: dial THIS extension to reach me, when you have an answer for me.
In jQuery, you'll use a parameter called "success" in the AJAX call.
Make success : function (data) { doSomething(data); } a part of that object that you're passing into the AJAX call.
When the file downloads, as soon as it downloads, jQuery will pass the results into the success function you gave it, which will do whatever it's made to do, or call whatever functions it was made to call.
Give it a try. It sure beats racing to see which downloads first.
I recommend not to use url: "./seeds/Ag.txt",, to target a file directly. Instead, use a server side script llike PHP to open the file and return the data, either in plane format or in JSON format.
You may find a tutorial to open files here: http://www.tizag.com/phpT/fileread.php