I'm trying to figure out the best way to do this...I am using JQuery to submit data to a PHP function, which sends back data from the DB as JSON, which is working. The thing is, on success, I want the JQuery to execute a PHP function...and I'd rather not have to make yet another AJAX call on top of the first AJAX success - especially since the php function is something I've already used elsewhere on my page. This is my code:
JQUERY:
$.ajax({
type: "POST",
url: post_url,
success: function(group) //we're calling the response json array 'tree'
{
//WANT TO CALL THE PHP FUNCTION HERE
} //end success
}); //end AJAX
PHP:
<?php
foreach($groups as $group){
echo '<option value="' . $group->id . '">' . $group->group_name . '</option>';
}
?>
In your php script that builds your response, just add an extra property to your object that is the html string you want to put into your page and then have javascript put it where it needs to go. You have no choice but to run php functions on the server.
If you want to call a php function from your javascript you will have to execute an AJAX request to the function, in its own file, on the server. This is because javascript executes client side and PHP executes server side. Therefore, javascript does not have direct access to PHP functions.
You can use your PHP to write JavaScript, or you can call a php file from a javascript via AJAX.
Can you replicate the functionality of the PHP function with a JavaScript function?
Would this, or something similar, work for you:
$.ajax({
type: "POST",
url: post_url,
success: function(groups) //we're calling the response json array 'tree'
{
for(group in groups){
document.writeln("<option value='"+groups[group].id+"'>"+groups[group].group_name+"</option>";
}
}
}); //end AJAX
Alternatives:
Change the PHP that backs the original AJAX call so that, instead of sending back JSON, it sends back HTML exactly as you want it.
Chain a second AJAX call "inside" the success of the first, so that a second round-trip to the server is done for the JSON->HTML conversion.
Accept that sometimes you need to "duplicate" presentation-rules when you are working with multiple languages, and use something like EJS to do the same <option> stuff that PHP does elsewhere.
You have to be aware that you're dealing with two paradigms here, the first one is server-side logic (PHP) and the second one is client-side logic (JavaScript).
Unfortunately there is no way to call PHP from JS from the client without performing an AJAX call and rendering the content you want to show. However, you could prepare the result and set the body of the AJAX response with your requested HTML string.
If this is not possible, I suggest to look at the diverse number of JS frameworks that will provide helpers to generate options for select fields.
Related
I have one quick question for experienced ones.
I have a page that does a jquery ajax post to another php page with javascript in it.
My question is, will the javascript get executed as well?
Another question.
lets say, that instead of javascript, I have another jquery ajax post request to a third php.
Will any of the 2 work?
Unless the javascript in that "another php page" is actually returned to the client and somehow inserted into the DOM, the JS cannot and will not execute. The resulting output of an AJAX operation is returned as a string to the code that performed the ajax call. It's not interpreted/parsed except in a few very specific cases.
If you're using jQuery's AJAX function to send POST variables to a PHP file, only the backend code will be executed. However, upon success of the AJAX call, you can execute some more JS code as follows
//Define whatever variables you want to pass along to the PHP file
var variable = "";
$.ajax({
url: "file.php",
type: "POST",
data: "variable="+ variable,
success: function(data)
{
//Upon success of the call, you can execute JS code here
}
});
Additional info here
I have form which generates content in a textarea box, and currently I'm passing the forms options as following:
function button_click() {
var columns = $('#form_id').val();
var url='generate.php?';
url+='&form_id='+encodeURIComponent(form_id);
$.ajax({
url: url,
beforeSend: function (xhr) {
xhr.overrideMimeType("application/json; charset=x-user-defined");
}
})
Then on the php page I have a request:
$form_id= $_REQUEST['form_id'];
Then I can use the variable how I wish in php.
It seems a bit redundant.
How can I condense this, if I make the form all php instead of using all ajax/json would that make a big difference?
If I understood your question correctly I would say that it is impossible to do what you want. The problem is that PHP script is executed on the server side, and javascript and form are handled by client side (browser).
So in general there is no way to get direct access from PHP to variables (elements) of your form/javascript. You can only pass these variables from the form by GET/POST HTTP request to server where you can handle them by your PHP script.
Ok so trying to get a page together that needs to connect to our SQL database. So on the javascript page I have functions that will autocomplete a textbox with data out of our mysql DB and then I need to send it to other functions and classes so that it will then look in our SQL DB and return some data. The problem I have is trying to get the .GET call to call in the php page, with the function that calls the class in which I need to get into for the SQL call. I have it setup somewhat but trying to figure out how to send the data through with it as well as just get clarification on how to work the .GET function.
Javascript page:
$.get("dsl_validate.php", calldsl(job));
Php Page
function calldsl($job){
var $dsljob = $job
hasfunctioncode($dsljob);
}
The hasfunctioncode function is in my DSL class page that will return the info I need. Any help on if I am in the right direction or not?
It looks like you're trying to physically call the PHP function calldsl() from the JavaScript. This... isn't right. (I'm assuming the $.get() you're using is from jQuery, please correct me if that assumption is incorrect.)
What $.get() does is simply call a resource on the web server. It doesn't have any knowledge of the server-side code (nor should it, for a number of reasons). From the perspective of the server-side code, there's no difference between a page being called via $.get() vs. one that's just loaded in a web browser.
What you essentially need to do is create a PHP page which accepts arguments either as a form post or query string (if you're using $.get() then the query string is the way to go), does its server-side logic, and then simply outputs the results to the "page." In the case of calling the page via AJAX as you are here, it's a good idea to render the page content using JSON notation. (Don't forget to set the content-type header to "application/json" as well.)
Then what you're getting on the client-side from the $.get() call is the response body, which would be that JSON data. It's really just a "page" like any other, the only difference is the content-type telling the browser that it's JSON data and that it doesn't have HTML, just JavaScript objects. The success callback on the $.get() call (the function you pass it, or create in-line) would receive that response data as an argument and can do what you need to with it.
The way I understand jQuery.get(), the second argument is the "callback" (http://api.jquery.com/jQuery.get/). The callback will hand the results from your server therefore should be a function. Currently your code actually executes the function "calldsl" where you should be only passing a reference like so...
Javascript:
$.get("dsl_validate.php", function(response){
alert("yay I haz ajax! "+response)
});
PHP: "dsl_validate.php"
echo "this is some data from the server";
No, your are not in the right direction. The first parameter of the get method have to br the complete URL of the page, not just the script (this works if the script resides on the same directory of the javascript file, though). The .php file shall return somehting "usable" for you javascript (JSON, or HTML, or text, or... whatever). The "calldsl" function will be called AFTER the data has been returned from the call. Something like that:
$.get('dsl_validate.php?value=somevalue', function(data) {
alert("Data returned from dsl_Validate: " + data)
});
i think you are better off passing the function as a param to your php page
$.get("dsl_validate.php?calldsl="+job, function(data) {
$response = $(data);// create a jquery object from the response
});
`
and in your php file
create a switch statement that call the function based on the parameter
Mmm I think you are wrong, the second argument on your get function is the javascript function that will process de data returned by "dsl_validate.php". I mean, if that page returns "foo", job will contain "foo".
But in my experience is better to use the autocomplete plugin from Jquery UI
jquery autocomplete plugin
I'm using jquery ajax can i use php code in success: function(html){} ??
No, jquery/JavaScript code is executed at the client side. You can either write JavaScript/jQuery code or preprocess the answer to the XHR request in php.
No, not directly, as JavaScript ist executed on the client side, and PHP is executed on the server.
A workaround would be to send another AJAX-Request from your success-function. But it can only do things on the server side, not on the client side.
If you just want to download a file from your callback function, use location.href = url. The URL can be a server side PHP script serving the data stream, or a real file.
Yes.
For instance, you could do:
success: function(html) {
<?php echo 'alert("Hello, World!");' ?>
}
Since JS is all client side and PHP is server side, the two cannot be executed within each other synchronously. However, you can use AJAX to ask PHP to execute code on values, but if you already have an AJAX query to PHP going, why not just do it then.
You use PHP indirectly anyhow. There is no need to note in the success function:
$.ajax({
url: "execute.php",
success: function(html){}
And the html comes directly from the execute.php script. And this is where you do any PHP stuff like:
<?php echo "<div>" . php_stuff() . "</div>"; ?>
Think of the PHP script as the first half of the execution, and the jQuery success: callback as the second part of the AJAX call.
I want to call a PHP function when pressing on a button, sort of like:
<?php
function output(){
// do something
}
?>
<input type="button" value="Enter" onclick="output()"/>
I tried to make something like:
<input type="button" value="Enter" onclick="test.php?execute=1"/>
where test.php is current page and then by php
<? if(isset(&execute)){ echo "Hello"; } ?>
but it doesn't work.
Since PHP runs on the webserver, and buttons (and JavaScript in this case) appear on the client, you have to make an HTTP request to the server.
The easiest way to do this is to use a form. No JavaScript is required. You can add JavaScript (although it should be layered on top of a working non-JS version). Using JavaScript to make an HTTP request without leaving the page is known as Ajax, and generally achieved with the XMLHttpRequest object. There are various libraries such as YUI and jQuery that can do some of the heavy lifting for you.
I think using an AJAX call would do sort of what you are asking. I don't know PHP very well but you can use the following example, and add another variable with the data you are passing in to the server to indicate which function you want to call on the server. On the server you can add some "IF" statements that will call a certain function based on the name passed in and return the result.
Here is what you could use on in your javascript client using the jQuery library as a helper to do the AJAX call:
<input type="button" value="Enter" onclick="output()"/>
<script type="text/javascript">
function output(){
$.ajax({
type: "POST",
url: "submit_data.php",
data: "username=" + "SomeUser"
+ "&email=" + "someEmail#google.com"
+ "&functionName=" + "theFunction1",
success: function(html){
alert('sucess! Result is:' + html);
}
});
}
</script>
and you can use code such as this to catch the data your javascript is passing in. In this example you would want to call this file name as "submit_data.php" to match the javascript above:
<?php
// Variables
$Username = $_POST['username'];
$Email = $_POST['email'];
$FunctionName = $_POST['functionName'];
//Add code here to choose what function to call and echo the result
// If $FunctionName equals 'theFunction1' then execute theFunction1
// If $FunctionName equals 'theFunction2' then execute theFunction2
echo "You called A Page!";
?>
Here I am doing nothing with the "username" and "email" simply grabbing it and storing them into holding variables. But you can easily add extra functionality here, such as checking for a name of a function that you want to run.
PHP is server side and javascript is client side. So I'm not sure if that is really what you want to be doing??
Perhaps you could explain why you want to specifically call a php function?
I googled PHP function from button and found this question on webdeveloper.com
It doesn't use Javascript.
This is PHP you're talking about, not ASP.NET. In PHP, there is no such thing as a button click event. PHP runs entirely on the server and has absolutely no knowledge of client-side events.
Your first try won't work because the PHP code only runs when the page first loads. It does not run when you call a JavaScript function. Your second example won't work because JavaScript and PHP can't talk directly to eachother like that. Trying to directly call a PHP function from JavaScript just doens't make sense. Remember, PHP only runs on the server. By the time you get to the point where JavaScript can run, the PHP code has long since completed its work.
If you want to do something when a button is clicked, you have to explicitly make a request back to the server. You can do this by just POSTing the form as CTphpnwb suggested. Just be aware that this will reload the page and you will have to manually save and restore the page state, e.g. repopulate input boxes. There is no built-in magic that will do this for you.
Alternatively, you can get all AJAXy and do the POST in JavaScript. However, you will have to write the JavaScript to send the request and process the response, and write the server-side PHP code to handle the request. This gets a little awkward to do in a single page.
From : http://www.dreamincode.net/forums/showtopic72353.htm
You cannot directly invoke a PHP function from Javascript this way :
PHP code is executed on the server
HTML / Javascript are interpreted on the client-side.
One the HTML page has been generated and sent to the client (the browser), there is nothing more PHP can do.
One solution would be to use an Ajax request :
Your onclick event would call a Javascript function
This Javascript function would launch an Ajax request : a request sent to the server
The server would then execute some PHP code
And, then, return the result of that execution to the client
And you'd be able to get that result in your Javascript code, and act depending on what was returned by the server.
There are plenty of solutions to do an Ajax request :
You can re-invent the wheel ; not that complex, I should say -- but see the next point
If already using a Javascript framework, like jQuery, Prototype, ... Those provide classes/methods/functions to do Ajax requests
Googling a bit will get you lots of tutorials/examples, about that ;-)