Extract part of HTML document in jQuery - ajax

I want to make an AJAX call to an HTML-returning page, extract part of the HTML (using jQuery selectors), and then use that part in my jQuery-based JavaScript.
The AJAX retrieval is pretty simple. This gives me the entire HTML document in the "data" parameter of the callback function.
What I don't understand is how to handle that data in a useful way. I'd like to wrap it in a new jQuery object and then use a selector (via find() I believe) to get just the part I want. Once I have that I'll be passing it off to another JavaScript object for insertion into my document. (This delegation is why I'm not using jQuery.load() in the first place).
The get() examples I see all seem to be variations on this:
$('.result').html(data);
...which, if I understand it correctly, inserts the entire returned document into the selected element. Not only is that suspicious (doesn't this insert the <head> etc?) but it's too coarse for what I want.
Suggestions on alternate ways to do this are most welcome.

You can use your standard selector syntax, and pass in the data as the context for the selector. The second parameter, data in this case, is our context.
$.post("getstuff.php", function(data){
var mainDiv = $("#mainDiv", data); // finds <div id='mainDiv'>...</div>
}, "html");
This is equivalent to doing:
$(data).find("#mainDiv");
Depending on how you're planning on using this, $.load() may be a better route to take, as it allows both a URL and a selector to filter the resulting data, which is passed directly into the element the method was called on:
$("#mylocaldiv").load("getstuff.php #mainDiv");
This would load the contents of <div id='mainDiv'>...</div> in getstuff.php into our local page element <div id='mylocaldiv'>...</div>.

You could create a div and then put the HTML in that, like this…
var div = $("<div>").html(data);
...and then filter the data like this…
var content = $("#content", div.get(0));
…and then use that.
This may look dangerous as you're creating an element and putting arbitrary HTML into it, but it's not: anything dangerous (like a script tag) will only be executed when it's inserted into the document. Here, we insert the data into an element, but that element is never put into the document; only if we insert content into the document would anything be inserted, and even then, only anything in content would be inserted.

You can use load on a new element, and pass that to a function:
function handle(element){
$(element).appendTo('body');
}
$(function(){
var div = $('<div/>');
div.load('/help a', function(){handle(div);});
});
Example: http://jsbin.com/ubeyu/2

You may want to look at the dataFilter() parameter of the $.ajax method. It lets you do operations on the results before they are passed out.
jQuery.ajax

You can do the thing this way
$.get(
url,
{
data : data
},
function (response) {
var page_content = $('.page-content',response).get(0);
console.log(page_content);
}
)
Here in the console.log you will see the inner HTML of the expected/desired portion from the response. Then you can use it as your wish

Related

How to check either the headline or the content should contain "FIFA" keyword?

How do I write this test in Cypress?
enter image description here
I have to confirm that either the headline or paragraph should contain the same keyword.
It's better to have JQuery elements in hand before the assertion so that you can use JQuery methods on them. cy.get() acts just like $(...) in JQuery, it will be enough to have the elements. (more here)
Once u have the elements, i.e. $el1 and $el2 below, then you can get their text via .text() method (more here) and then you can write your assertion.
Instead of a separate assertion, below I used a single one and checked if either of them includes the desired text by using || operator.
cy.get('first-el').then($el1 => {
cy.get('second-el').then($el2 => {
const inEl1 = $el1.text().includes('FIFA');
const inEl2 = $el2.text().includes('FIFA');
expect(inEl1 || inEl2).to.be.true;
});
});

Loading external csv file in jsfiddle

I am trying to create a jsfiddle for one of the dc.js examples. I am not able to load an external file using a URL and d3.csv().
Can someone please suggest how to load a csv file using d3.csv in jsfiddle.
The approach I usually use for CSV data in JSFiddle examples is
a. Put the data in a <pre> block at the end of the HTML mark-up, usually with the id "data".
b. Add pre {display:none;} to the CSS.
c. Replace the d3.csv(filename, callback) function call with a d3.csv.parse(text) call, using the text content of the <pre> block as the input to the parse function.
Because the parse function doesn't use a callback, it just returns the data array, you need to save that output in a variable of the same name as your callback data parameter.
In other words, if your example looks like
d3.csv("data.csv", function(error, data) {
if(error){console.log("Could not read " + "data.csv");
/* Do something with `data` here */
});
The JSFiddle-friendly version would look like:
//d3.csv("data.csv", function(error, data) {
// if(error){console.log("Could not read " + "data.csv");
var data = d3.csv.parse( d3.select("pre#data").text() );
/* Do something with `data` here */
//});
If you would rather have a full working example that uses the file-reading methods as intended, there are other options as mentioned in the comments. Tributary also allows external data files I think.

WordPress Pagination not working with AJAX

I'm loading some posts though AJAX and my WordPress pagination is using the following function to calculate paging:
get_pagenum_link($paged - 1)
The issue is that the pagination is getting created through AJAX so it's making this link look like: http://localhost:1234/vendor_new/wp-admin/admin-ajax.php
However the actual URL that I'm trying to achieve is for this:
http://localhost:1234/vendor_new/display-vendor-results
Is there a way to use this function with AJAX and still get the correct URL for paging?
I can think of three options for you:
To write your own version of get_pagenum_link() that would allow you to specify the base URL
To overwrite the $_SERVER['REQUEST_URI'] variable while you call get_pagenum_link()
To call the paginate_links() function, return the whole pagination's HTML and then process that with JS to only take the prev/next links.
#1 Custom version of get_pagenum_link()
Pros: you would have to change a small amount of your current code - basically just change the name of the function you're calling and pass an extra argument.
Cons: if the function changes in the future(unlikely, but possible), you'd have to adjust your function as well.
I will only post the relevant code of the custom function - you can assume everything else can be left the way it's in the core version.
function my_get_pagenum_link( $pagenum = 1, $escape = true, $base = null ) {
global $wp_rewrite;
$pagenum = (int) $pagenum;
$request = $base ? remove_query_arg( 'paged', $base ) : remove_query_arg( 'paged' );
So in this case, we have one more argument that allows us to specify a base URL - it would be up to you to either hard-code the URL(not a good idea), or dynamically generate it. Here's how your code that handles the AJAX request would change:
my_get_pagenum_link( $paged - 1, true, 'http://localhost:1234/vendor_new/display-vendor-results' );
And that's about it for this solution.
#2 overwrite the $_SERVER['REQUEST_URI'] variable
Pros: Rather easy to implement, should be future-proof.
Cons: Might have side effects(in theory it shouldn't, but you never know); you might have to edit your JS code.
You can overwrite it with a value that you get on the back-end, or with a value that you pass with your AJAX request(so in your AJAX request, you can have a parameter for instance base that would be something like window.location.pathname + window.location.search). Difference is that in the second case, your JS would work from any page(if in the future you end-up having multiple locations use the same AJAX handler).
I will post the code that overwrites the variable and then restores it.
// Static base - making it dynamic is highly recommended
$base = '/vendor_new/display-vendor-results';
$orig_req_uri = $_SERVER['REQUEST_URI'];
// Overwrite the REQUEST_URI variable
$_SERVER['REQUEST_URI'] = $base;
// Get the pagination link
get_pagenum_link( $paged - 1 );
// Restore the original REQUEST_URI - in case anything else would resort on it
$_SERVER['REQUEST_URI'] = $orig_req_uri;
What happens here is that we simply override the REQUEST_URI variable with our own - this way we fool the add_query_arg function into thinking, that we're on the /vendor_new/display-vendor-results page and not on /wp-admin/admin-ajax.php
#3 Use paginate_links() and manipulate the HTML with JS
Pros: Can't really think of any at the moment.
Cons: You would have to adjust both your PHP and your JavaScript code.
Here is the idea: you use paginate_links() with it's arguments to create all of the pagination links(well - at least four of them - prev/next and first/last). Then you pass all of that HTML as an argument in your response(if you're using JSON - or as part of the response if you're just returning the HTML).
PHP code:
global $wp_rewrite, $wp_query;
// Again - hard coded, you should make it dynamic though
$base = trailingslashit( 'http://localhost:1234/vendor_new/display-vendor-results' ) . "{$wp_rewrite->pagination_base}/%#%/";
$html = '<div class="mypagination">' . paginate_links( array(
'base' => $base,
'format' => '?paged=%#%',
'current' => max( 1, $paged ),
'total' => $wp_query->max_num_pages,
'mid_size' => 0,
'end_size' => 1,
) ) . '</div>';
JS code(it's supposed to be inside of your AJAX success callback):
// the html variable is supposed to hold the AJAX response
// either just the pagination or the whole response
jQuery( html ).find('.mypagination > *:not(.page-numbers.next,.page-numbers.prev)').remove();
What happens here is that we find all elements that are inside the <div class="mypagination">, except the prev/next links and we remove them.
To wrap it up:
The easiest solution is probably #2, but if someone for some reason needs to know that the current page is admin-ajax.php while you are generating the links, then you might have an issue. The chances are that no one would even notice, since it would be your code that is running and any functions that could be attached to filters should also think that they are on the page you need(otherwise they might mess something up).
PS: If it was up to me, I was going to always use the paginate_links() function and display the page numbers on the front-end. I would then use the same function to generate the updated HTML in the AJAX handler.
This is actually hard to answer without specific details of what and how is being called. I bet you want to implement that in some kind of endless-sroll website, right?
Your best bet is to get via AJAX the paginated page itself, and grab the related markup.
Assume you have a post http://www.yourdomain.com/post-1/
I guess you want to grab the pagination of the next page, therefore you need something like this:
$( "#pagination" ).load( "http://www.yourdomain.com/post-1/page/2 #pagination" );
This can easily work with get_next_posts_link() instead of get_pagenum_link().
Now, in order for your AJAX call to be dynamic, you could something like:
$( "#pagination" ).load( $("#pagination a").attr('href') + " #pagination" );
This will grab the next page's link from your current page, and load its pagination markup in place of the old.
It's also doable with get_pagenum_link() however you'd need to change the $("#pagination a").attr('href') selector appropriately, in order to get the next page (since you'd have more than one a elements inside #pagination

Seaside: list losing its content on update

This one is really simple. I've got a <select> and I want to update some internal state based on the selection. No need to redisplay anything. The problem is that after the selection and the AJAX request have been made, the list loses its contents.
renderContentOn: html
|value myId|
html form with: [
html select list: #('one' 'two' 'tree' 'four' 'five');
id: (myId := html nextId);
callback: [ :v | value := myId ];
onChange: (
html prototype updater
triggerFormElement: myId;
callback: [:h | value "do something with the value here"];
return: false
).
]
The #updater needs an DOM ID of the element to update. If you fail to provide an ID, it default to this, the DOM element triggering the event. Thus, you end up with an empty list. If you do not need to update something you should use #request instead of #updater. If you want to update something you need to provide a valid ID using #id:.
Read the section AJAX: Talking back to the Server of the Seaside Book, it explains AJAX in great detail.
Because the updater replaces the html of the element it was defined on with the content generated by the callback and your callback does not generate any html, the list is empty, I think.

Google AJAX Transliteration API: Is it possible to make all input fields in the page transliteratable?

I've used "Google AJAX Transliteration API" and it's going well with me.
http://code.google.com/apis/ajaxlanguage/documentation/referenceTransliteration.html
Currently I've a project that I need all input fields in every page (input & textarea tags) to be transliteratable, while these input fields differs from page to page (dynamic).
As I know, I've to call makeTransliteratable(elementIds, opt_options) method in the API call to define which input fields to make transliteratable, and in my case here I can't predefine those fields manually. Is there a way to achieve this?
Thanks in advance
Rephrasing what you are asking for: you would like to collect together all the inputs on the page which match a certain criteria, and then pass them into an api.
A quick look at the API reference says that makeTransliteratable will accept an array of id strings or an array of elements. Since we don't know the ids of the elements before hand, we shall pass an array of elements.
So, how to get the array of elements?
I'll show you two ways: a hard way and an easy way.
First, to get all of the text areas, we can do that using the document.getElementsByTagName API:
var textareas = document.getElementsByTagName("textarea");
Getting the list of inputs is slightly harder, since we don't want to include checkboxes, radio buttons etc. We can distinguish them by their type attribute, so lets write a quick function to make that distinction:
function selectElementsWithTypeAttribute(elements, type)
{
var results = [];
for (var i = 0; i < elements.length; i++)
{
if (elements[i].getAttribute("type") == type)
{
results.push(elements[i]);
}
}
return results;
}
Now we can use this function to get the inputs, like this:
var inputs = document.getElementsByTagName("input")
var textInputs = selectElementsWithTypeAttribute(textInputs, "text");
Now that we have references to all of the text boxes, we can concatenate them into one array, and pass that to the api:
var allTextBoxes = [].concat(textareas).concat(textInputs);
makeTransliteratable(allTextBoxes, /* options here */);
So, this should all work, but we can make it easier with judicious use of library methods. If you were to download jQuery (google it), then you could write this more compact code instead:
var allTextBoxes = $("input[type='text'], textarea").toArray();
makeTransliteratable(allTextBoxes, /* options here */);
This uses a CSS selector to find all of the inputs with a type attribute of "text", and all textareas. There is a handy toArray method which puts all of the inputs into an array, ready to pass to makeTransliteratable.
I hope this helped,
Douglas

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