When we use AJAX for validation the response comes through xml file and in case of javascript the response comes through html page.
Is it true or false ?
please explian both the cases.
Ajax can return pretty much anything. Your particular application or implementation might be returning XML, but Ajax commonly returns JSON and HTML as well. But it can return TXT or just status codes ..
AJAX is such a broad term that both of your cases can be called like that. Basically every call from already loaded page is AJAX even if it's done by dynamically creating tag or refreshing iframe.
actually Ajax is nothing but a term to describe what is happening, the response comes as an xml or html depending on what you want it to return, it is a string that ajax returns, in Javascript it is up to you what to do with that string, want to parse it as XML node? want to display it immidiately in an element "innerHMTL" or want to alert the returned string... the power of ajax is not what it returns, it is what it does on the server (remotly) without having to send the whole page in.
AJAX there can be any type of return text. With Javascript it can work on the DOM object and get anything from the page.
The main difference, AJAX a request goes to the server and the result is returned.
Related
For a website, which doesn't use AJAX I'm using OnDocumentComplete event to know when the page loading is complete.
My question is, how can I detect when website, which uses AJAX requests is ready (e.g. when a website which is fetching some search results by using AJAX finished its work) ?
Ok here is a trick i developed my self.
1-in your html page make a div and set its text to "false".
2-in you server side put a javascript at the end of your returning code. for example your site returns following text upon an ajax call.
a
b
c
d
e
so after this text put a javascript code that will change the text of div from "false" to "true"
so what will happen is that once you receive all the data from ajax call you will also receive the javascript code and that code will run and set the value of div.
so in your page once all data is received you will see the indicator div. and you will know that you have received all data. you can also run functions in similar way upon completion of data.
I want to create a page with will be filled with dynamic info using Ajax (JQuery). The info will come from various GETs I need to do in other URLs.
I'll be using Sinatra + JQuery to to that, but as my WEB experience is almost null and don't have any idea how do to it right.
The requisites for this are:
Each time a GET completes, a new line of information should appear on the page.
If the GET could not be complete, a default info appear on the page.
My idea so far is to do something like this:
Have my controller performing each GET inside a thread.
Each time a thread ends, with success or not, I inform the view of the result and render a partial
I'll have as many partial as I need (for each GET I must do)
The first time I load the page I fill in the default info, them I update via AJAX with the successful GET responses
This does not seem the correct approach, so I'm asking someone that already did something similar or has more experience on this some help.
You start off with a simple get('/'){} route that holds the default message (or any other GET route). Then you have your other GET routes that you want to display on your default route. In Sinatra you can check whether a request is an xhr-request or not with a request.xhr? If you have an xhr request you return a json value to your view, otherwise reject the request or render a view with proper html. This is on your sinatra backend. In your views you can use JQuery or any other JS library or plain JS to handle asynchronous data requests. You can use the ajax function in JQuery to request data from your routes and then add them to your DOM. It's as simple as that :)
Now you will have to investigate on the JQuery site how to make ajax requests and how to append data to existing DOMs. That's all there is to it.
What is the best way to address an AJAX script that sends data to POST in codeigniter? Right now I am loading a view with the AJAX through $this->load->view('AJAX', $data); however there is no UI or user actions in the view. It's simply running through the script and returning POST data a little after the script loads. I receive the POST data in my model where I input the values into the DB and output some other values based on the data.
I need to open a real view, set metatags and re-direct the user to another website afterwards.
How do I address this?
The problem I'm facing is that I cannot open up another view because the AJAX view is the one that's in focus but I need this AJAX view to be temporary that basically does it's thing and sends to POST.
Is there any convention that I can lookup/research to what I'm describing? Let me know what kind of clarification is needed if any.
Some people like to write "ajax" controllers and post to them exclusively, but you don't need to do that. You can handle the request in the same controller that handles the non-ajax request. Personally, I exclusively return json, but you can return chunks of HTML if that works better for you.
Your exact problem is vague (actual code would help clarify), but I think you are on the wrong track. Don't use a view for processing anything ever. Use your Controller layer, this is for handling input and requests.
Example of controller method responding to either ajax or non-ajax request:
function edit_user()
{
$data['status'] = $this->user_model->save();
if ($this->input->is_ajax_request())
{
// return json string with our update status
// Something like: {"status":true}
echo json_encode($data);
exit;
}
// Load the non ajax view with the same data
$this->load->view('users/edit', $data)
}
$this->input->is_ajax_request() is a function of the Input class that reads $_SERVER['HTTP_X_REQUESTED_WITH'] and checks if it's value is XMLHttpRequest. This should only be true if it's an "ajax" request.
You can make life easier by wrapping this in a class or function. No matter what you decide to do, don't use the view layer for processing data.
I think my problem is, how do I address javascript without a view? how do I call the script and/or where do I put the JS code in the controller? I felt it was the wrong direction to address the code in a view but I didn't see how else to do it.
Whenever possible, you should put javascript code in a .js file and use a <script> tag to load it, in an HTML document. The only other exception is putting it in a "view" file (a file that's only purpose is to construct your final HTML output). In other words, follow the same rules of HTML as to where to put javascript, and follow the usual conventions of MVC of where HTML belongs (in the view). Javascript code does not belong in your controller. Javascript is not processing your data, it is sending the data to the server.
I need to open a real view, set metatags and re-direct the user to another website afterwards.
If you want to load a view, then redirect (after a certain amount of time I assume), you can do it with javascript or a <meta> tag (but don't use a meta tag, use js).
After processing a jQuery Ajax Post from an HTML form successfully within a Go program, how do I load a new form? I first tried sending the form as the response and the Javascript displayed it, but it did not clear the old (existing) form. I then tried within the HTML Javascript to set the URL using "window.location = 'localhost:8088/MaintForm/'". That resulted in a warning from the browser but did not load the form and did not change the URL. I would like to ideally know both methods - via the Go program acting as a server, and via Javascript. If I manually change the URL, the form loads OK. What I am trying to do is receive a response in Javascript (jQuery Ajax), and then request the new form if the response is positive. I would prefer to do this without changing the URL. As I said above, this partially worked.
You would have to put your original form inside a tag, for example a div, and use your JQuery code to replace the contents of that tag with the new form. This way you are not changing the URL.
This is more of a javascript/JQuery question than a go-specific one.
In javascript:
location.href = '/MaintForm/';
In golang, you can use the http.Redirect function, like this:
http.Redirect(w, r, "/MaintForm/", http.StatusFound)
Please note: this appears to be solved by : I just need to do an "document.write(data);" in Javascript. "Data" contains the new HTML.
A XHR call returns HTML, how do I tell the browser to use that and reload the entire page? I know the main use for XHR is to do partial page fresh but my case is a bit special. Thanks.
Or put it in a more general term, what is the best way to use JS to simulate a browser form GET request? window.location.replace("url")?
rather than trying to reload or something, have you considered doing something like
document.body.innerHTML = [the string HTML that you got back from XHR];
Or perhaps you could do it by building a new DOM from the HTML and then swapping it in?