basically I am trying to call a javascript function from my PHP and I am using code I know works in other situations however here is it not and I am at a loss as to why?
It may be something stupid as I have been staring at this screen for a long time :)
here is where I call the function:
if(isset($test_details['done_test'])){
echo "getting here";
echo "<SCRIPT LANGUAGE='javascript'>user_error();</SCRIPT>";
}
I successfully get 'getting here' printed however it does not call the JS function.
javascript function:
function user_error(){
document.write("working");
//alert("User has already taken this test. Your are being redirected...");
//setTimeout("window.location='home_student.php'",3000);
}
The commented it what I do eventually want it to do.
Could anyone please shed some light.
Many thanks,
#Crimson - Here is what I tried after your advice...still no luck.
javascript now:
$(document).ready(function () {
var done = "<?= $test_details['done_test'] ?>";
if(typeof done != 'undefined'){
$('WORKING').appendTo('#bodyArea'); // just to test
}
});
By echoing <script>...</script> with PHP, you are not going to get the browser run the JS function!
PHP only outputs the HTML file that you want to send to the browser. The browser then parses this HTML and does a multitude of things before the page is displayed to the user.
Next, the user interacts with the displayed page (or some other browser related event like 'onload' happens) and the attached JS gets called.
So, if there is some JS that you want to run at a certain time, say immediately after the browser has finished loading the page, you need to create JS in the HTML file such that there is a JS function which gets called at the page load event like this:
<body onload="/*do something here*/"> ... </body>
It is better to use JQuery or some other JS frmework to accomplish something like this though.
Are you sure the function is already defined? Perhaps you declared your function after making the function call.
Additionally, although it's not really going to matter here, the proper way to have a javascript script tag is.
<script type="text/javascript"></script>
i.e. not language="javascript"
Replace the line you call the JS function with this:
echo '<script type="text/javascript">window.onload = user_error </script>' ;
It should solve the problem. Because at the time you are calling user_error(), the function may not have been initialized by the browser. So you'll get an error since the function could not be found.
If the function is placed in an external .js file, it's very likely that you get this error, since the external file usually takes a while to be loaded. If the function deceleration is in the same file but after where you are calling it, same thing happens.
Related
I have a bit of code in a div which needs to be refreshed every few seconds.
If I use a PHP include, the page works fine, but obviously can't be refreshed.
When I use a jquery load, none of my PHP functions work within the included file and none of the php variables are recognised. Any help would be hugely appreciated!
<script type="text/javascript">
function refreshPosts() {
$('div#refresh').load('/include/included_file.php');
setTimeout("refreshPosts()",1000);
}
</script>
<script type="text/javascript">
$(document).ready(function() {
refreshPosts();
});
</script>
In my php file, there are calls to various functions, which result in this:
Fatal error: Call to undefined function myFunction()
Since you did not add any code or helpful errors, we can only speculate on problem. My guess is the problem is the following:
Your main page has in it's php code some includes, or some object instantiations, which does not exist on your "jquery loaded" (I guess you mean an ajax request by that) page. I'm about 90% sure this is your problem, but can't give more details since... well... lack of things to go on.
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.
I'm creating a webpage using php, mysql, html5&css3 and javascript (ajax).
To improve the performance, i decided to use AJAX to get only the content div (<div id="content">) that actually changes, i dont want to reload the whole code all the time. That works as follows: after having received the new content from a php-file, javascript does the following:
document.getElementById("content").innerHTML = new_content;
After that, the new_content is well displayed...
Now the Problem:
In the new_content, i have some javascript, too, e.g.:
<script type="text/javascript" lang="JAVASCRIPT">
alert('Hello!');
...
</script>
Unfortunately, when inserting it in the div, it isn't executed at all...when calling the php-file "naturally", the javascript code does what i want it to do, so there's no error in it.
Thanks in advance
EDIT: Problem is solved, i included jquery:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js">
</script>
and used $("#content").html(new_content); in javascript as mentioned below.
Use jQuery's $.html. It will automatically execute scripts for you.
$("#content").html(new_content);
Indeed, by default script execution is disabled when just replacing HTML - makes sense if you look at it. You should really consider using a library like jQuery or Mootools to abstract issues like this away.
If you look at Mootools' Request.HTML implementation you'll see it has its evalScripts option defaulting to true, which later on during the call results in this bit of code being executed:
response.html = text.stripScripts(function(script){
response.javascript = script;
});
...
if (options.evalScripts) Browser.exec(response.javascript);
However this probably won't work on its own without Mootools' other bits of browser-abstracting code in place, so yes I'd definitely recommend including a library on your project.
for the life of me I cannot get my PHP file to be called using the ajax function. Here is my relevant HTML:
$(document).ready( function(){
$("#generate").click(function(){
alert("Been clicked");
$.ajax({
url: "filterScriptForMe.php",
success: function(data){
alert("response");
}
});
});
});
Here is my PHP file, which I can run by calling separately, and will print to the error log/echo/create the necessary image no problem when run on it's own:
error_log("script has been called");
$hello = imagecreatefrompng("./images/stock.png");
$hello = imagecreatefrompng("./images/stock.png");
imagealphablending($hello,false);
imagesavealpha($hello,true);
$x=imagecolorallocatealpha($hello,0,0,0,127);
$color = imagecolorat($hello,350,500);
for($y=0;$y<512;$y++)
for($z=0;$z<597;$z++)
{
if($color!=imagecolorat($hello,$y,$z))
{
imagesetpixel($hello,$y,$z,$x);
}
}
imagepng($hello,"done.png");
echo "done";
I am beginning to wonder if there is a problem on my server at this point. When run it will print the first alert saying "been clicked" but it does not seem to be running the php script as I get no output to my log files when clicking the button from the html file, as opposed to visiting the php directly in the broswer. Both the html and php are in the same directory, and I have double checked the names to make sure they are correct.
I know other jQuery functions are working on the page as well, as I've been successful in getting some jQueryUI elements to display and respond to manipulation using jQuery alone. Added to that the first alert seems to be firing, so I'm fairly sure the library/code is in there. I've tried going through with firebug, but it's a little beyond me when it starts getting deep into the library and I lose track of what's being done and why.
Any help that you can provide would be much appreciated, at least to get the PHP file called from the html page. Thanks!
Here is what I am trying to accomplish. I have a form that uses jQuery to make an AJAX call to a PHP file. The PHP file interacts with a database, and then creates the page content to return as the AJAX response; i.e. this page content is written to a new window in the success function for the $.ajax call. As part of the page content returned by the PHP file, I have a straightforward HTML script tag that has a JavaScript file. Specifically:
<script type="text/javascript" src="pageControl.js"></script>
This is not echoed in the php (although I have tried that), it is just html. The pageControl.js is in the same directory as my php file that generates the content.
No matter what I try, I can't seem to get the pageControl.js file included or working in the resulting new window created in response to success in the AJAX call. I end up with errors like "Object expected" or variable not defined, leading me to believe the file is not getting included. If I copy the JavaScript directly into the PHPfile, rather than using the script tag with src, I can get it working.
Is there something I am missing here about scope resolution between calling file, php, and the jQuery AJAX? I am going to want to include javascript files this way in the future and would like to understand what I am doing wrong.
Hello again:
I have worked away at this issue, and still no luck. I am going to try and clarify what I am doing, and maybe that will bring something to mind. I am including some code as requested to help clarify things a bit.
Here is the sequence:
User selects some options, and clicks submit button on form.
The form button click is handled by jQuery code that looks like this:
$(document).ready(function() {
$("#runReport").click(function() {
var report = $("#report").val();
var program = $("#program").val();
var session = $("#session").val();
var students = $("#students").val();
var dataString = 'report=' +report+
'&program=' +program+
'&session=' +session+
'&students=' +students;
$.ajax({
type: "POST",
url: "process_report_request.php",
cache: false,
data: dataString,
success: function(pageContent) {
if (pageContent) {
$("#result_msg").addClass("successMsg")
.text("Report created.");
var windowFeatures = "width=800,menubar=yes,scrollbars=1,resizable=1,status=yes";
// open a new report window
var reportWindow = window.open("", "newReportWindow", windowFeatures);
// add the report data itself returned from the AJAX call
reportWindow.document.write(pageContent);
reportWindow.document.close();
}
else {
$("#result_msg").addClass("failedMsg")
.text("Report creation failed.");
}
}
}); // end ajax call
// return false from click function to prevent normal submit handling
return false;
}); // end click call
}); // end ready call
This code performs an AJAX call to a PHP file (process_report_request.php) that creates the page content for the new window. This content is taken from a database and HTML. In the PHP file I want to include another javascript file in the head with javascript used in the new window. I am trying to include it as follows
<script src="/folder1/folder2/folder3/pageControl.js" type="text/javascript"></script>
Changed path folder names to protect the innocent :)
The pageControl.js file is actually in the same folder as the jQuery code file and the php file, but I am trying the full path just to be safe. I am also able to access the js file using the URL in the browser, and I can successfully include it in a static html test page using the script src tag.
After the javascript file is included in the php file, I have a call to one of its functions as follows (echo from php):
echo '<script type="text/javascript" language="javascript">writePageControls();</script>';
So, once the php file sends all the page content back to the AJAX call, then the new window is opened, and the returned content is written to it by the jQuery code above.
The writePageControls line is where I get the error "Error: Object expected" when I run the page. However, since the JavaScript works fine in both the static HTML page and when included "inline" in the PHP file, it is leading me to think this is a path issue of some kind.
Again, no matter what I try, my calls to the functions in the pageControls.js file do not work. If I put the contents of the pageControl.js file in the php file between script tags and change nothing else, it works as expected.
Based on what some of you have already said, I am wondering if the path resolution to the newly opened window is not correct. But I don't understand why because I am using the full path. Also to confuse matters even more, my linked stylesheet works just fine from the PHP file.
Apologies for how long this is, but if anyone has the time to look at this further, I would greatly appreciate it. I am stumped. I am a novice when it comes to a lot of this, so if there is just a better way to do this and avoid this problem, I am all ears (or eyes I suppose...)
I have also had problems with a similar issue to this, and this was a real headache. The following approach may not be elegant, but it worked for me.
Make sure that your php file, just outputs what you want in your
body
Add jquery to the window head dynamically
Add any external script files to the window head dynamically
use jQuery html on the window's document to call html() with your loaded content on the body, so that scripts are evaluated.
For example, in your ajax success:
success: function(pageContent) {
var windowFeatures = "width=800,menubar=yes,scrollbars=1,resizable=1,status=yes";
var reportWindow = window.open("", "newReportWindow", windowFeatures);
// boilerplate
var boilerplate = "<html><head></head><body></body></html>";
reportWindow.document.write(boilerplate);
var head = reportWindow.document.getElementsByTagName("head")[0];
var jquery = reportWindow.document.createElement("script");
jquery.type = "text/javascript";
jquery.src = "http://code.jquery.com/jquery-1.7.min.js";
head.appendChild(jquery);
var js = reportWindow.document.createElement("script");
js.type = "text/javascript";
js.src = "/folder1/folder2/folder3/pageControl.js";
js.onload= function() {
reportWindow.$("body").html(pageContent);
};
head.appendChild(js);
reportWindow.document.close();
}
Good luck!
It probably isn't looking where you think it is looking to grab your javascript file.
Try a server-relative format like this:
<script src="/some/path/to/pageControl.js"></script>
If that still isn't working, verify that you can type the url to your script file into your browser and get it to download.
Make sure that you have that within either <head> or <body> of the HTML page. Also, I'd double check the path to the .js file. You could do that by pasting "pageControl.js" at the root of your web address.
Things to look for:
Use Firebug (NET tab) to check if the js file is loaded with status 200. Also check in the Console tab for any javascript errors.
Are you using HTML5 offline. If you do, maybe it serves a cached version that doesn't include your <script> tag.
View the page source and make sure it includes the script tag.
Change the source attribute to absolute path: <script src="http://www.example.com/js/pageControl.js" type="text/javascript"></script>
Visit http://www.example.com/js/pageControl.js and make sure it shows correctly.
Try to place the <script> right after the <head> so that it loads first.
This is all I could think of.
You can dynamically load script by creating the element and then append it to head or other element:
reportWindow.document.write(pageContent);
var script = document.createElement('script');
script.src = 'pageControl.js';
script.type = 'text/javascript';
reportWindow.document.getElementsByTagName('head')[0].appendChild(script);
reportWindow.document.close();
Have you tried using the jquery $("#target_div").load(...)
This also executes JS inside the output...
Read this doc to find out how to use it :
http://api.jquery.com/load/
To me it sounds like you're expecting an unloaded script to work.
Try taking a look here: http://ensure.codeplex.com/SourceControl/changeset/view/9070#201379
This is a bit of javascript that ensures that the script is loaded properly before access is attempted. You can use this either as lazy loading (loading javascript files only when required), or, as I interpret your problem, loading a script based on the result of ajax calls.
What's probably happening is, you're echoing a string via an ajax callback, not inserting an element. External scripts require a second GET call to load their contents, which isn't happening - only the first call happened. So, when the first call includes the inline code, the DOM doesn't have to make an additional GET request to fetch the contents. If the DOM doesn't see the script, the DOM won't execute it, which means it's just some random tag.
There's a very fast way to find out. In Chrome (or Firefox with the Firebug plugin installed), check the console > scripts dropdown to see all the loaded scripts. If it's not listed, it's not loaded and the script tag you see in the markup is otherwise inert.
Since it's probably just a string as far as PHP cares, you could create it as PHP DOM object and insert it properly (although this could be laborious). Instead, maybe place it at the very end of the page, just before the closing body tags. (This is the preferred position for js anyway - dead last, after all the other elements on the page have loaded and are available to the DOM.)
HTH :)