I have following workflow
div on the page is used
on users operation request is done
to server side page whose html is
retrived using ajax and dumped into
the div
With html markup some JavaScript is
also dumped however that is not
getting executed.
Why is so ? What could be the possible fix ?
Though i avoid doing things like this but in some old code implementations like these are very common.
Scripts added using .innerHTML will not be executed, so you will have to handle this your self.
One easy way is to extract the scripts and execute them
var response = "html\<script type=\"text/javascript\">alert(\"foo\");<\/script>html";
var reScript = /\<script.*?>(.*)<\/script>/mg;
response = response.replace(reScript, function(m,m1) {
eval(m1); //will run alert("foo");
return "";
});
alert(response); // will alert "htmlhtml"
This will extract the scripts, execute them and replace them with "" in the original data.
Related
I want to use a click to delete eror_log file on server
In the code below why I'm getting html of currently viewing page as a response?
This happens regardles error_log exists or not
I'm expecting empty string as a response
$('.btnmoto').on('contextmenu', function(e){
e.preventDefault();
$.post('aa.php', {fn: 'del_erlog'}, function(data){
console.log(data); // html of current page
});
});
aa.php
function del_erlog(){
if (is_file('error_log')) {
unlink('error_log');
}
}
In the code below why I'm getting html of currently viewing page as a response?
Because that is what the PHP is outputting.
I assume that somewhere in the PHP you have some code along the lines of
if ($_POST['fn'] === 'del_erlog') {
del_erlog();
}
But that doesn't stop the rest of the code in the file running.
You would need an exit statement or similar to do that.
(I don't recommend mixing Ajax handling code and HTML document generating code in the same file though, it makes things harder to manage in general).
I'm trying to load the JSON before anything else loads, because I need to access the JSON immediately when a browser connects to the server.
This is how I load my json
$.getJSON('icons.txt', function(iconData) {
icons = iconData;
});
How can I make it so javascript loads the json first before anything else? or at least makes it so that it's loaded before the user connects.
Just put all your other code inside function(iconData) {icons = iconData;}); callback function, it will be executed after the JSON will be fetched.
If you put your tag in the head of your HTML, it should be executed at first.
Maybe duplicate of: Load javascript before rendering page?
The code loaded on the head, and then set to synchronize loading
$.ajaxSettings.async = false;
$.getJSON(url, data, function(data){ });
Well i wanna create an Ajax Drag and Drop Shopping cart using only javascript and ajax. Currently i'm using the example in this page as a stepping stone. Right now it's only with local jquery and it works fine but i want to make the cart work with ajax calls. Note that i do not want to use a server side language( like php, rubby, asp etc), only html and javascript.
My initial thought was that at the $(".basket").droppable i should add an ajax call to another html page containing the "server logic" in javascript, execute in that file all the necessary steps( like reading the get variables (product name, product id and quantity), set a cookie and then return an ok response back. When the server got the "ok" response it should "reload" the cart div with the updated info stored inside the cookie.
If this was with php i would know how to do it. The problem is that as far as i know, you can execute javascript once it reaches the DOM, but how can you execute that js from inside the page that isbeing called upon ? ( thanks to Amadan for the correction)
I've thought about loading the script using $.getScript( "ajax/test.js", function( data, textStatus, jqxhr ).. but the problem with that is that the url GET variables i want to pass to the "server script" do not exist in that page.
I havent implemented all the functionality yet as i am stuck in how to first achieve javascript execution inside an ajax target page.
Below is a very basic form of my logic so far
// read GET variables
var product = getQueryVariable("product");
var id = getQueryVariable("id");
var quantity= getQueryVariable("quantity");
//To DO
//--- here eill go all the logic regarding cookie handling
function getQueryVariable(variable) {
var query = window.location.search.substring(1);
var vars = query.split("&");
for (var i=0;i<vars.length;i++) {
var pair = vars[i].split("=");
if (pair[0] == variable) {
return pair[1];
}
}
alert('Query Variable ' + variable + ' not found');
}
Any help regarding this matter will be appreciated.
Note: Logic in simple words:
1)have an html page with products+cart
2)Have an "addtocart.html" with the "Cart Server Logic"( being the target of the ajax call when an item is dropped into the product.)
If you have some other idea on this, please enlighten me :)
thanks in advance
Foot Note-1:
if i try loading the scipt using
$("#response").load("ajax/addtocart.html?"+ $.param({
product: product,
id: id,
quantity:quantity
})
);
i get the alert about not being able to find the url parameters( something that i thing is normal as because the content is being loaded into the initial page, from which the request is started, there are no get parameters in the url in the first place)
The problem is that as far as i know, you cannot execute javascript contained in the target of an ajax call, as that page never reaches the browser interpreter.
This is either incorrect or misleading. The browser will execute any JavaScript that enters DOM. Thus, you can use $.load to load content and execute code at the same time. Alternately, you can use hacked JSONP to both execute code and also provide content as a JSON document.
EDIT: Yes, you can't get to the AJAX parameters from JavaScript. Why do you want to? Do you have a good reason for it, or is it an XY problem?
The way I'd do it is this:
$('#response').load(url, data, function() {
onAddedToCart(product, id, quantity);
});
and wrap your JS code in your HTML into the onAddedToCart function.
Depending on what exactly you're doing, it could be simplified even further, but this should be enough to cover your use case.
I have a basic html file which is attached to a java program. This java program updates the contents of part of the HTML file whenever the page is refreshed. I want to refresh only that part of the page after each interval of time. I can place the part I would like to refresh in a div, but I am not sure how to refresh only the contents of the div. Any help would be appreciated. Thank you.
Use Ajax for this.
Build a function that will fetch the current page via ajax, but not the whole page, just the div in question from the server. The data will then (again via jQuery) be put inside the same div in question and replace old content with new one.
Relevant function:
http://api.jquery.com/load/
e.g.
$('#thisdiv').load(document.URL + ' #thisdiv');
Note, load automatically replaces content. Be sure to include a space before the id selector.
Let's assume that you have 2 divs inside of your html file.
<div id="div1">some text</div>
<div id="div2">some other text</div>
The java program itself can't update the content of the html file because the html is related to the client, meanwhile java is related to the back-end.
You can, however, communicate between the server (the back-end) and the client.
What we're talking about is AJAX, which you achieve using JavaScript, I recommend using jQuery which is a common JavaScript library.
Let's assume you want to refresh the page every constant interval, then you can use the interval function to repeat the same action every x time.
setInterval(function()
{
alert("hi");
}, 30000);
You could also do it like this:
setTimeout(foo, 30000);
Whereea foo is a function.
Instead of the alert("hi") you can perform the AJAX request, which sends a request to the server and receives some information (for example the new text) which you can use to load into the div.
A classic AJAX looks like this:
var fetch = true;
var url = 'someurl.java';
$.ajax(
{
// Post the variable fetch to url.
type : 'post',
url : url,
dataType : 'json', // expected returned data format.
data :
{
'fetch' : fetch // You might want to indicate what you're requesting.
},
success : function(data)
{
// This happens AFTER the backend has returned an JSON array (or other object type)
var res1, res2;
for(var i = 0; i < data.length; i++)
{
// Parse through the JSON array which was returned.
// A proper error handling should be added here (check if
// everything went successful or not)
res1 = data[i].res1;
res2 = data[i].res2;
// Do something with the returned data
$('#div1').html(res1);
}
},
complete : function(data)
{
// do something, not critical.
}
});
Wherea the backend is able to receive POST'ed data and is able to return a data object of information, for example (and very preferrable) JSON, there are many tutorials out there with how to do so, GSON from Google is something that I used a while back, you could take a look into it.
I'm not professional with Java POST receiving and JSON returning of that sort so I'm not going to give you an example with that but I hope this is a decent start.
You need to do that on the client side for instance with jQuery.
Let's say you want to retrieve HTML into div with ID mydiv:
<h1>My page</h1>
<div id="mydiv">
<h2>This div is updated</h2>
</div>
You can update this part of the page with jQuery as follows:
$.get('/api/mydiv', function(data) {
$('#mydiv').html(data);
});
In the server-side you need to implement handler for requests coming to /api/mydiv and return the fragment of HTML that goes inside mydiv.
See this Fiddle I made for you for a fun example using jQuery get with JSON response data: http://jsfiddle.net/t35F9/1/
Usefetch and innerHTML to load div content
let url="https://server.test-cors.org/server?id=2934825&enable=true&status=200&credentials=false&methods=GET"
async function refresh() {
btn.disabled = true;
dynamicPart.innerHTML = "Loading..."
dynamicPart.innerHTML = await(await fetch(url)).text();
setTimeout(refresh,2000);
}
<div id="staticPart">
Here is static part of page
<button id="btn" onclick="refresh()">
Click here to start refreshing every 2s
</button>
</div>
<div id="dynamicPart">Dynamic part</div>
$.ajax(), $.get(), $.post(), $.load() functions of jQuery internally send XML HTTP request.
among these the load() is only dedicated for a particular DOM Element. See jQuery Ajax Doc. A details Q.A. on these are Here .
I use the following to update data from include files in my divs, this requires jQuery, but is by far the best way I have seen and does not mess with focus. Full working code:
Include jQuery in your code:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script>
Create the following function:
<script type="text/javascript">
function loadcontent() {
$("#test").load("test.html");
//add more lines / divs
}
</script>
Load the function after the page has loaded; and refresh:
<script type="text/javascript">
$( document ).ready(function() {
loadcontent();
});
setInterval("loadcontent();",120000);
</script>
The interval is in ms, 120000 = 2 minutes.
Use the ID you set in the function in your divs, these must be unique:
<div id="test"></div><br>
There is a similar post Retrieving HTTP status code from loaded iframe with Javascript but the solution requires the server-side to return javascript calling a function within the iframe. Instead, I would simply like to check the HTTP status code of the iframe without having to call a function within the iframe itself since my app either returns the full site through HTML or the single object as JSON. Essentially I've been trying to implement a callback method which returns success|failure dependent upon the HTTP status code.
Currently I have uploadFrame.onLoad = function() { ... so far pretty empty ... } and I am unsure what to check for when looking for HTTP status codes. Up until now, I've mainly relied upon jQuery's $.ajax() to handle success|failure but would like to further understand the mechanics behind XHR calls and iframe use. Thanks ahead of time.
UPDATE
The solution I came up with using jQuery
form.submit(function() {
uploadFrame.load(function() {
//using eval because the return data is JSON
eval( '(' + uploadFrame[0].contentDocument.body.children[0].innerHTML + ')' );
//code goes here
});
});
I think the best solution is injecting <script> tag into your iframe <head> and insert your "detecting" javascript code there.
something like this:
$('#iframeHolderDivId').html($.get('myPage.php'));
$('#iframeHolderDivId iframe head').delay(1000).append($('<script/>').text('your js function to detect load status'));
Maybe it's not the best solution but I think it works