jQuery GET function does not execute.
I am using a Telerik Data grid that executes the following script when a row is selected
<script type="text/javascript">
function onRowSelected(e) {
IPAddressId = e.row.cells[0].innerHTML;
var dialogDiv = $('#result');
var viewUrl = '/IPAddresses/Edit/' + IPAddressId;
$.get(viewUrl, function (data) {
alert(viewUrl);
});
};
</script>
I have the alert inside the .get function for testing. I actually have other code I will place in there.
If I place the alert(viewUrl) above the $.get function, the alert displays however as it is shown above the alert does not get displayed.
Your $.get is correct.
It's possible you are getting a 500 error, and you didn't specify an error function to get called, so you never see it. Open your console (Firebug, Chrome Developer tools, etc) and go to the 'net panel'. What does it say?
The function(data){ alert( viewUrl ) } is a callback function . It will be excuted when the ajax request obtain the server correct response .
So you should debug this, use firefox's firebug extension ，or use chrome developer tool. Watch the newwork panel , and lookup this request , is it have been responsed with http code "200"?
Related
I want the data coming from the server to show in the <div id="demo"> element.
But sometimes, it just appears and goes, and other times, it is not even showing up. I searched and tried lots of options, but nothing works for me.
My code is:
function loadDoc(){
document.getElementById("demo").innerHTML = "Paragraph changed!";
alert("hello world");
$.ajax({
type:'POST',
url :"new_mark.php",
data :"regno=u4cse13xxx",
success: function(data) {
//$("demo").html = "Narayana!";
document.getElementById("demo").innerHTML = data;
alert(data);
}
});
}
To debug an web site, i advise you tu use the Chrome debugger or on generaly the browser debugger its very simple and usefull.
Click F12 and go to ressources and put an debug point at your line and it finished
Just call the Element and set the the content via a jquery method like text (Reference: .text())
So your code inside success would be:
success: function(data) {
$("#demo").text(data);
}
And maybe you can tell me if it worked? :)
Greets!
Go to the Network tab of the debugger, select your request (new_mark.php), then check the Response tab. If there was an error, it should appear in the response.
For example in Chrome:
Is there a way I can run a php function through a JS function?
something like this:
<script type="text/javascript">
function test(){
document.getElementById("php_code").innerHTML="<?php
query("hello"); ?>";
}
</script>
<a href="#" style="display:block; color:#000033; font-family:Tahoma; font-size:12px;"
onclick="test(); return false;"> test </a>
<span id="php_code"> </span>
I basically want to run the php function query("hello"), when I click on the href called "Test" which would call the php function.
This is, in essence, what AJAX is for. Your page loads, and you add an event to an element. When the user causes the event to be triggered, say by clicking something, your Javascript uses the XMLHttpRequest object to send a request to a server.
After the server responds (presumably with output), another Javascript function/event gives you a place to work with that output, including simply sticking it into the page like any other piece of HTML.
You can do it "by hand" with plain Javascript , or you can use jQuery. Depending on the size of your project and particular situation, it may be more simple to just use plain Javascript .
Plain Javascript
In this very basic example, we send a request to myAjax.php when the user clicks a link. The server will generate some content, in this case "hello world!". We will put into the HTML element with the id output.
The javascript
// handles the click event for link 1, sends the query
function getOutput() {
getRequest(
'myAjax.php', // URL for the PHP file
drawOutput, // handle successful request
drawError // handle error
);
return false;
}
// handles drawing an error message
function drawError() {
var container = document.getElementById('output');
container.innerHTML = 'Bummer: there was an error!';
}
// handles the response, adds the html
function drawOutput(responseText) {
var container = document.getElementById('output');
container.innerHTML = responseText;
}
// helper function for cross-browser request object
function getRequest(url, success, error) {
var req = false;
try{
// most browsers
req = new XMLHttpRequest();
} catch (e){
// IE
try{
req = new ActiveXObject("Msxml2.XMLHTTP");
} catch(e) {
// try an older version
try{
req = new ActiveXObject("Microsoft.XMLHTTP");
} catch(e) {
return false;
}
}
}
if (!req) return false;
if (typeof success != 'function') success = function () {};
if (typeof error!= 'function') error = function () {};
req.onreadystatechange = function(){
if(req.readyState == 4) {
return req.status === 200 ?
success(req.responseText) : error(req.status);
}
}
req.open("GET", url, true);
req.send(null);
return req;
}
The HTML
test
<div id="output">waiting for action</div>
The PHP
// file myAjax.php
<?php
echo 'hello world!';
?>
Try it out: http://jsfiddle.net/GRMule/m8CTk/
With a javascript library (jQuery et al)
Arguably, that is a lot of Javascript code. You can shorten that up by tightening the blocks or using more terse logic operators, of course, but there's still a lot going on there. If you plan on doing a lot of this type of thing on your project, you might be better off with a javascript library.
Using the same HTML and PHP from above, this is your entire script (with jQuery included on the page). I've tightened up the code a little to be more consistent with jQuery's general style, but you get the idea:
// handles the click event, sends the query
function getOutput() {
$.ajax({
url:'myAjax.php',
complete: function (response) {
$('#output').html(response.responseText);
},
error: function () {
$('#output').html('Bummer: there was an error!');
}
});
return false;
}
Try it out: http://jsfiddle.net/GRMule/WQXXT/
Don't rush out for jQuery just yet: adding any library is still adding hundreds or thousands of lines of code to your project just as surely as if you had written them. Inside the jQuery library file, you'll find similar code to that in the first example, plus a whole lot more. That may be a good thing, it may not. Plan, and consider your project's current size and future possibility for expansion and the target environment or platform.
If this is all you need to do, write the plain javascript once and you're done.
Documentation
AJAX on MDN - https://developer.mozilla.org/en/ajax
XMLHttpRequest on MDN - https://developer.mozilla.org/en/XMLHttpRequest
XMLHttpRequest on MSDN - http://msdn.microsoft.com/en-us/library/ie/ms535874%28v=vs.85%29.aspx
jQuery - http://jquery.com/download/
jQuery.ajax - http://api.jquery.com/jQuery.ajax/
PHP is evaluated at the server; javascript is evaluated at the client/browser, thus you can't call a PHP function from javascript directly. But you can issue an HTTP request to the server that will activate a PHP function, with AJAX.
The only way to execute PHP from JS is AJAX.
You can send data to server (for eg, GET /ajax.php?do=someFunction)
then in ajax.php you write:
function someFunction() {
echo 'Answer';
}
if ($_GET['do'] === "someFunction") {
someFunction();
}
and then, catch the answer with JS (i'm using jQuery for making AJAX requests)
Probably you'll need some format of answer. See JSON or XML, but JSON is easy to use with JavaScript. In PHP you can use function json_encode($array); which gets array as argument.
I recently published a jQuery plugin which allows you to make PHP function calls in various ways: https://github.com/Xaxis/jquery.php
Simple example usage:
// Both .end() and .data() return data to variables
var strLenA = P.strlen('some string').end();
var strLenB = P.strlen('another string').end();
var totalStrLen = strLenA + strLenB;
console.log( totalStrLen ); // 25
// .data Returns data in an array
var data1 = P.crypt("Some Crypt String").data();
console.log( data1 ); // ["$1$Tk1b01rk$shTKSqDslatUSRV3WdlnI/"]
I have a way to make a Javascript call to a PHP function written on the page (client-side script). The PHP part 'to be executed' only occurs on the server-side on load or refreshing'. You avoid 'some' server-side resources. So, manipulating the DOM:
<?PHP
echo "You have executed the PHP function 'after loading o refreshing the page<br>";
echo "<i><br>The server programmatically, after accessing the command line resources on the server-side, copied the 'Old Content' from the 'text.txt' file and then changed 'Old Content' to 'New Content'. Finally sent the data to the browser.<br><br>But If you execute the PHP function n times your page always displays 'Old Content' n times, even though the file content is always 'New Content', which is demonstrated (proof 1) by running the 'cat texto.txt' command in your shell. Displaying this text on the client side proves (proof 2) that the browser executed the PHP function 'overflying' the PHP server-side instructions, and this is because the browser engine has restricted, unobtrusively, the execution of scripts on the client-side command line.<br><br>So, the server responds only by loading or refreshing the page, and after an Ajax call function or a PHP call via an HTML form. The rest happens on the client-side, presumably through some form of 'RAM-caching</i>'.<br><br>";
function myPhp(){
echo"The page says: Hello world!<br>";
echo "The page says that the Server '<b>said</b>': <br>1. ";
echo exec('echo $(cat texto.txt);echo "Hello world! (New content)" > texto.txt');echo "<br>";
echo "2. I have changed 'Old content' to '";
echo exec('echo $(cat texto.txt)');echo ".<br><br>";
echo "Proofs 1 and 2 say that if you want to make a new request to the server, you can do: 1. reload the page, 2. refresh the page, 3. make a call through an HTML form and PHP code, or 4. do a call through Ajax.<br><br>";
}
?>
<div id="mainx"></div>
<script>
function callPhp(){
var tagDiv1 = document.createElement("div");
tagDiv1.id = 'contentx';
tagDiv1.innerHTML = "<?php myPhp(); ?>";
document.getElementById("mainx").appendChild(tagDiv1);
}
</script>
<input type="button" value="CallPHP" onclick="callPhp()">
Note: The texto.txt file has the content 'Hello world! (Old content).
The 'fact' is that whenever I click the 'CallPhp' button I get the message 'Hello world!' printed on my page. Therefore, a server-side script is not always required to execute a PHP function via Javascript.
But the execution of the bash commands only happens while the page is loading or refreshing, never because of that kind of Javascript apparent-call raised before. Once the page is loaded, the execution of bash scripts requires a true-call (PHP, Ajax) to a server-side PHP resource.
So, If you don't want the user to know what commands are running on the server:
You 'should' use the execution of the commands indirectly through a PHP script on the server-side (PHP-form, or Ajax on the client-side).
Otherwise:
If the output of commands on the server-side is not delayed:
You 'can' use the execution of the commands directly from the page (less 'cognitive' resources—less PHP and more Bash—and less code, less time, usually easier, and more comfortable if you know the bash language).
Otherwise:
You 'must' use Ajax.
I am doing a get request on a page ie: url.com, then checking whether something exists on it. If the info I am looking for exists I open a blank page and put the contents of the get request onto the blank page via document.write.
Tampermonkey doesn't recognize that a script needs to be run when I update it via win.history.pushState, so nothing gets executed. Is there another way to accomplish this?
$.get(url,
function(data)
{
var win=window.open('',"_blank");
win.history.pushState({ 'page_id': 1}, "newpage", "https://www.url.com/stuff/"); //this line doesn't work
with(win.document){
open();
write(data);
close();
}
}
)
Trying to get a very simple request working with MooTools Request.JSON. After having no success building it from scratch, I took an example from somewhere and slowly pared it down to the bare, bare minimum, then put it back into my own page. The only things changed are the url and element ID, but to no avail.
Any help, ideas, will be greatly appreciated.
json.php
<?php
$result['name'] = 'yay';
header('Content-type: application/json');
echo json_encode($result);
?>
demo.js (snippet inside window.addEvent('domready', function() { )
$(document.body).getElement('input[id=game_name]').addEvents({
'keydown' : function(){
alert('hmm'); //this fires
var jsonRequest = new Request.JSON({
url: "json.php",
onComplete: function(result){ //changing to onSuccess kills everything afterwards
alert('result.name'); //this fires
alert(result.name); //this does not fire
alert('result.name'); //this does not fire
}
}).get();
}
});
PS. in neither my page, or the pared down example pages, can i get the request to send on domready, only inside an event. why is that?
thanks again
As it turns out, the problem was that I had accidentally loaded a synced duplicate file into my browser that was therefore (obviously) unable to execute anything server side.
Thank you very much for your help.
Several suggestions/questions:
Are you getting any errors in your web browser's console? Which web browser are you using? The fact that the third alert doesn't fire at all suggests that alert(result.name); is throwing an error, in which case, all further execution will be stopped and an error will appear on your browser's console.
When you say "changing to onSuccess kills everything afterwards", what exactly do you mean? Does code further down (i.e. code that's not included in the above code snippet) never execute? Or does onSuccess just never fire?
Is json.php in the same directory as the page where this script is running? Try replacing json.php in url: "json.php" with an absolute URL (/mydirectory/json.php or http://www.mywebsite.com/mydirectory/json.php) and see whether this works.
If it's any help, the following code results in an alert reading "yay" (running on a local server; json.php is a file containing the PHP code in your question):
var jsonRequest = new Request.JSON({
url: "json.php",
onSuccess: function(result) {
alert(result.name);
}
}).get();
you can find a great tutorial here
http://net.tutsplus.com/tutorials/javascript-ajax/checking-username-availability-with-mootools-and-request-json/
Exactly the same problem here.
I solved it by decoding the JSON string, which is given as parameter (instead of the expected object).
onSuccess: function(jsonString) {
console.log(JSON.decode(jsonString));
}
Here ist the documentation:
http://mootools.net/docs/core/Utilities/JSON#JSON:decode
I have a page where I need to add a drag and drop functionality to certain elements. When the drop event occurs, it makes an ajax call to a php function and then refreshes the contents of a div. I'm using jQuery with jQueryUI for the drag and drop, and CakePHP as a PHP framework (not sure if this is relevant).
Everything is working just fine in Firefox, Safari and even IE, but in Opera or Chrome the contents of the div isn't refreshed (although the action from the PHP function is executed).
So, here is the code:
jQuery('#lists div').
filter(function() {return this.id.match(/item[\d]+_[\d]+/);}).
each(function() { jQuery(this).draggable( {axis: 'y'}); });
jQuery('#lists div').
filter(function() {
return this.id.match(/list[\d]+/);}).
each(function() {
jQuery(this).droppable({
drop: function(event, ui) {
dropID = jQuery(event.target).attr('id');
dragID = jQuery(ui.draggable).attr('id');
itemID = dragID.substr(dragID.lastIndexOf('_') + 1);
oldListID = dragID.substr(4).replace(/_[\d]+/g, '');
newListID = drop.substr(4);
jQuery.ajax({
url: "/lists/itemToList/"+itemID+"/"+oldListID+
"/"+newListID,
type: "POST",
success: function (data) {
jQuery('#lists').html(data);}
});
}
});
});
Basically, the success function isn't executed, but if I try to see the errorThrown (on the error event) it is "undefined"
Try something like this:
jQuery.ajax({
url: "/lists/itemToList/"+itemID+"/"+oldListID+
"/"+newListID,
type: "POST",
success: function (data) {
jQuery('#lists').html(data);
}
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(XMLHttpRequest.status);
alert(XMLHttpRequest.responseText);
}
});
It will show you what http response are you getting for your request. I had the same problem some time ago. My script worked great in Firefox and Chrome, but it didn't do anything in Opera and IE. I checked it and the problem was, that the php backend was returning 404 (I still don't know how did it work under Chrome and FF).
I know it's been a long time since I've posted the question, but here is what I found to be the solution, in case somebody else needs it: the problem was not the in javascript but with CakePHP: the html that was added on success contained an ajax form (rendered using $ajax->form()). $ajax->form() needed the $data variable from the controller to be an array, but for some reason it wasn't, and this broke the rendering of the form, and Opera and Chrome didn't like this. So the solution was to simply add
$this->data = array();
to the itemToList() function in my controller.
I don't see anything in the code that would cause a cross browser issue. My feeling is that it's a problem doesn't lie in the code at all, but in the rendering of the div and/or its contents in Chrome and Opera (i.e. a CSS problem or something along those lines where the innerHTML of the div is updated, but because of styling or positioning you don't get the visual result you were looking for).
Have you checked using Dragonfly or some other developer tool to verify that the contents of the target element are in fact unchanged after a successful request? Along those lines have you tried stepping through the code execution in the problem browsers? You could also try adding a error handler to the JQuery.ajax options to see if there is some problem with the request itself, although I don't believe that is where the problem lies.
EDIT: I didn't see that last bit below the code block. So you have verified that the success handler isn't being executed. You said that you did try and implement an error handler for the request and got some undefined result, but I don't see it in the code. Could you post the code for the error handler and describe what in the error is undefined?
I think he means, that alert(errorThrown) is showing 'undefined'.