We Keep Coding

javascript value to php [duplicate]

This question already has answers here:
How do I pass JavaScript variables to PHP?
(16 answers)
Closed 3 years ago.
First I thought that I had to convert JavaScript to PHP, but then I found out that I cannot because of server and client side executions. So now I simply want to send ONE variable
<script type="text/javascript">
function scriptvariable()
{
var theContents = "the variable";
}
</script>
to a PHP variable
<?php
$phpvariable
?>
That function in the JavaScript executes when let's say I click on a button.
Now I have no idea on how to assign that phpvariable to the JavaScript one to use the phpvariable to look up stuff in my database. I know I can add it to my url or some thing and refresh the page, but I would like to do it with AJAX as I might have to use this Ajax method further in my webpage.
So is there an easy way to do this without having to dump pages of code on my page to do one simple thing?

PHP runs on the server and Javascript runs on the client, so you can't set a PHP variable to equal a Javascript variable without sending the value to the server. You can, however, set a Javascript variable to equal a PHP variable:
<script type="text/javascript">
var foo = '<?php echo $foo ?>';
</script>
To send a Javascript value to PHP you'd need to use AJAX. With jQuery, it would look something like this (most basic example possible):
var variableToSend = 'foo';
$.post('file.php', {variable: variableToSend});
On your server, you would need to receive the variable sent in the post:
$variable = $_POST['variable'];

As Jordan already said you have to post back the javascript variable to your server before the server can handle the value. To do this you can either program a javascript function that submits a form - or you can use ajax / jquery. jQuery.post
Maybe the most easiest approach for you is something like this
function myJavascriptFunction() {
var javascriptVariable = "John";
window.location.href = "myphpfile.php?name=" + javascriptVariable;
}
On your myphpfile.php you can use $_GET['name'] after your javascript was executed.

It depends on the way your page behaves. If you want this to happens asynchronously, you have to use AJAX. Try out "jQuery post()" on Google to find some tuts.
In other case, if this will happen when a user submits a form, you can send the variable in an hidden field or append ?variableName=someValue" to then end of the URL you are opening. :
http://www.somesite.com/send.php?variableName=someValue
or
http://www.somesite.com/send.php?variableName=someValue&anotherVariable=anotherValue
This way, from PHP you can access this value as:
$phpVariableName = $_POST["variableName"];
for forms using POST method or:
$phpVariableName = $_GET["variableName"];
for forms using GET method or the append to url method I've mentioned above (querystring).

How to pass javascript variables to php variables with yii

First: I KNOW this is a duplicate. I am creating this because none of the answers to all the other questions satisfy me. I have a very particular situation where I'm using yii and tryi I can't send it through ajax because the php and javascript are on the same page on the same page.
Basically what I'm asking is if you have a page that uses yii and chart js, and you need to render a page that requires two arguments from the clicked bar, which is represented by activeBars[0]:
<script>
canvas.onclick = function(event) {
var activeBars = getBarsAtEvent(event);
<?php $controller->functionThatRendersView($arg1 /**(activeBars[0].value*/,$arg2 /**(activeBars[0].label*/); ?>
}
I don't care if it will render automatically, that is another problem. I just need to get those arguments to the php.
Thanks.
Also, if it helps, I am passing those two values to javascript through php for loops:
labels: [<?php for ($i=1;$i<=$numberIssues;$i++) {
echo $i . ",";
}?>],
The problem with grabbing $i and putting it into the label argument is that I don't know which bar label is the clicked one, I need javascript to pass the clicked bar values back to php.

Explain to us again why you can't use ajax. You say "because the php and javascript are on the same page". That's not what ajax is - you need a different URL for the ajax request, and a separate PHP file or something to handle it.
Without ajax it's impossible for javascript to send information to PHP, because the PHP runs on the server before the javascript runs on the client. Unless of course you want to do a complete page refresh, which is slower and generally worse from the user perspective.

I found an answer to my question! I'm just doing this for anyone else who is stumbling:
To pass javasctipt variable var jsInteger = 5; to php you type (in javascript):
window.location.href = "yourPhpFile.php?phpInteger="+jsInteger;
You access the variable in php like so:
$phpInteger = $_GET['phpInteger'];
This will require a page refresh, and will redirect you to the php file.

inside javascript assigning javascript variable into php variable [duplicate]

This question already has answers here:
How do I pass JavaScript variables to PHP?
(16 answers)
Closed 3 years ago.
First I thought that I had to convert JavaScript to PHP, but then I found out that I cannot because of server and client side executions. So now I simply want to send ONE variable
<script type="text/javascript">
function scriptvariable()
{
var theContents = "the variable";
}
</script>
to a PHP variable
<?php
$phpvariable
?>
That function in the JavaScript executes when let's say I click on a button.
Now I have no idea on how to assign that phpvariable to the JavaScript one to use the phpvariable to look up stuff in my database. I know I can add it to my url or some thing and refresh the page, but I would like to do it with AJAX as I might have to use this Ajax method further in my webpage.
So is there an easy way to do this without having to dump pages of code on my page to do one simple thing?

PHP runs on the server and Javascript runs on the client, so you can't set a PHP variable to equal a Javascript variable without sending the value to the server. You can, however, set a Javascript variable to equal a PHP variable:
<script type="text/javascript">
var foo = '<?php echo $foo ?>';
</script>
To send a Javascript value to PHP you'd need to use AJAX. With jQuery, it would look something like this (most basic example possible):
var variableToSend = 'foo';
$.post('file.php', {variable: variableToSend});
On your server, you would need to receive the variable sent in the post:
$variable = $_POST['variable'];

As Jordan already said you have to post back the javascript variable to your server before the server can handle the value. To do this you can either program a javascript function that submits a form - or you can use ajax / jquery. jQuery.post
Maybe the most easiest approach for you is something like this
function myJavascriptFunction() {
var javascriptVariable = "John";
window.location.href = "myphpfile.php?name=" + javascriptVariable;
}
On your myphpfile.php you can use $_GET['name'] after your javascript was executed.

It depends on the way your page behaves. If you want this to happens asynchronously, you have to use AJAX. Try out "jQuery post()" on Google to find some tuts.
In other case, if this will happen when a user submits a form, you can send the variable in an hidden field or append ?variableName=someValue" to then end of the URL you are opening. :
http://www.somesite.com/send.php?variableName=someValue
or
http://www.somesite.com/send.php?variableName=someValue&anotherVariable=anotherValue
This way, from PHP you can access this value as:
$phpVariableName = $_POST["variableName"];
for forms using POST method or:
$phpVariableName = $_GET["variableName"];
for forms using GET method or the append to url method I've mentioned above (querystring).

Using javascript variable in PHP with ajax [duplicate]

This question already has answers here:
Passing Javascript Variable to PHP using Ajax
(2 answers)
Closed 8 years ago.
I am thinking to use Speedof.me api to find out the user download speed accurately.I will use the value of the download speed to determine which video quality will be used to stream video to the user.
<html>
<head>
<script src="http://speedof.me/api/api.js" type="text/javascript"></script>
</head>
<body>
<h2>SpeedOf.Me API Consumer - Sample Page</h2>
<script type="text/javascript">
SomApi.account = "SOM5380125e96067"; //your API Key here
SomApi.domainName = "domain.com"; //your domain or sub-domain here
SomApi.config.sustainTime = 2;
SomApi.onTestCompleted = onTestCompleted;
SomApi.onError = onError;
SomApi.startTest();
function onTestCompleted(testResult) {
var speed = testResult.download;
}
</script>
<?php
//how can i use the speed variable here
}
?>
</body>
</html>
I am a begineer with javascript and i would like to use the javascript variable in the php as shown above without reloading the page.I know that javascript is executed client-side and php is server-side but from what i read online is that ajax is the way to go.Also is there a way in which i can store the result of speedof.me so that i don't need to run the test every time the same user view a video
Thanks for helping me out guys

you can make an ajax call to server to use the javascript variable in php
function onTestCompleted(testResult) {
var speed = testResult.download;
$.ajax({
url:"link to php script" // e.g test/index.php
type:"POST", //method to send data
dataType:"json", //expected data from server
data:{speed:speed}, //data to send server
success:function(data){
alert(data); //alert response data after ajax call success
}
});
}
on php script you can use that javascript variable speed after checking $_POST[]
echo $_POST['speed'];

passing PHP values to javascript can just be echoed. But javascript to PHP is a bit complicated.
Server scripts like PHP are executed first before Browser scripts (i.e. javascript) do their job. this means, after the page has loaded, your php won't do any good anymore, EXCEPT, you use Ajax requests.
what I use is jquery function .post() (if you're wondering why i use post, you can do your own reading about this functions including .ajax() and .get() )
PHP code somewhere found in /project/execute.php
$speed = $_POST["speed"];
echo $speed * 5;
and in your javascript...
<script type="text/javascript">
SomApi.account = "SOM5380125e96067"; //your API Key here
SomApi.domainName = "domain.com"; //your domain or sub-domain here
SomApi.config.sustainTime = 2;
SomApi.onTestCompleted = onTestCompleted;
SomApi.onError = onError;
SomApi.startTest();
function onTestCompleted(testResult) {
var speedresult = testResult.download;
// here's the magic
$.post("/project/execute.php", {speed:speedresult}, function(result) {
alert(result);
} )
}
PS. DON'T FORGET TO IMPORT JQUERY IN YOUR SECTION OR THE BOTTOM MOST PART OF THE BODY
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

You do not seem to understand the fundamental differences between Clientside and Serverside Code.
The PHP Code will be executed serverside; only the output is sent to the browser. Then the browser executes the Javascript.
One solution to your problem would be to load the video dynamically with Javascript (either per Ajax or a simple video link naming convention). To store the speed test results, use a Cookie.

It doesn't work that way. As you said, JavaScript is client side. Your PHP page is processed by the server first--meaning, all PHP code gets executed first before any of your HTML, CSS, and JS. It doesn't matter if your JS is positioned first before PHP since PHP will get evaluated first. After that, it's sent back to the client for the browser to process HTML, CSS, and JS.
For your case, after running the speed test, send the value back to a PHP script via AJAX. You can use jQuery to make AJAX calls easier. Store a cookie using JS to indicate that the test has been executed once. You'll need to modify your JS so that it will check if this cookie is present and skip the speed test.

try this :-
<?php
echo "<script>alert(speed)</script>";
?>

CodeIgniter function breaks with Javascript

I'm using CodeIgniter form helper, and this is what it does:
Uncaught SyntaxError: Unexpected token ILLEGAL
The code:
jQuery('#window-1').append('<?= form_dropdown('hfdata', $hf_arr, set_value('hfdata'), 'class="span3"') ?>');
As you can see, I'm using a PHP inside of a JS, when I do <?= 'Test' ?> it works.
So it seems like its related with the CodeIgniter function.
As far as i know this error message can be caused by unknown/wrong characters in the code, and from what I saw in the firebug, this CI function is generating text with tabs and line breaks... and that is my problem I guess.
I may be wrong, so please correct me if so.
I will appreciate any solution for this problem.

Chances are you're screwing up your quotes and you need to change the way you're passing that last parameter to the dropdown.
$class = 'class="span3"';
jQuery('#window-1').append('<?= form_dropdown("hfdata", $hf_arr, set_value("hfdata"), $class) ?>');

To explain how PHP and Javascript works: Php is executed on the server, this give html output. You browser will get that output and can do anything with it. From this point javascript can do his job.
You are echoing the php function call to the users browser. Javascript can't call the php function. If you want to do this, then you need to make a php file call that returnes the result you want. But I guess there is an other problem. ( if you want to do this, escape the ' characters)
You need to execute the PHP code on the server. This will give a result. You send this result to the client. On the clients PC javascript will execute your javascript code.
If you want to generate with PHP the javascript code, then you can do something like this ( in PHP on the server!):
jQuery('#window-1').append('<?= form_dropdown('hfdata', $hf_arr, set_value('hfdata')); ?> ');
If this isn't what you want, then you are working on a design problem. Then it's a kind of dead end.

I found the answer myself... As I said, it was caused by the HTML output that was returned from the from_dropdown.
The solution is simple, remove all unwanted characters like line breaks:
<?php
$prepare = preg_replace('/^\s+|\n|\r|\s+$/m', '', form_dropdown('hfdata', $hf_arr, set_value('hfdata'), 'class="span3"'));
?>
jQuery('#window-1').append('<?= $prepare ?>');