Update records without refresh - javascript

Apologies if this has been asked before but I'm not sure what to search for exactly so I thought it would be better to explain it.
I am using php to get records from a mysql table and present them. However I have added couple of dropdowns and search boxes to filter out the results and I would like to do it without refreshing the page. Can anyone point me to a tutorial or something like that? I guess I should use jQuery but as I said I don't know what to look for exactly.
Thank you!

You need to use AJAX at client side:
Here are few good examples:
http://www.w3schools.com/php/php_ajax_database.asp
Using Jquery Ajax to retrieve data from Mysql

You can use ajax in jQuery.
Here is a quick look at the ajax API.
And a tutorial guide for ajax:
http://learn.jquery.com/ajax/
And a tutorial for getting started with jquery ajax call
http://www.keyboardninja.eu/webdevelopment/jquery-ajax-call-tutorial

AJAX is a technique for creating fast and dynamic web pages. AJAX allows web pages to be updated asynchronously by exchanging small amounts of data with the server behind the scenes. This means that it is possible to update parts of a web page, without reloading the whole page.
The XMLHttpRequest object is part of a technology called Ajax (Asynchronous JavaScript and XML). Using Ajax, data could then be passed between the browser and the server, using the XMLHttpRequest API, without having to reload the web page
You can get AJAX Examples Here

Related

How can I make JavaScript calls to scrape data from a website?

I'll try to explain everything the way I understand it as clearly as possible, so correct me if I'm confused with something.
I was trying to scrape the users from a member list on a website, I used Python and the first thing I did was making a post request to the Request URL with the required headers so I get a response that contains the data I need but this didn't work, so I tried to find out the reason.
From what I understand now the website uses AJAX to make XHR and JavaScript calls which respond with the content (users).
The JS code is stored on a static website from what Chrome's developer tool request initiators
tell me (Here is an image for reference), which responds with the HTML that contains the users
The idea is to create a script that runs this static JS script that's stored online and fetch the data about the users from it. (Image for clarification)
How do I achieve this, I'm using python. What libraries do I need etc.? Any help/advice is greatly appreciated!
Based on your questions, I think you're trying to load data from a website that uses AJAX to load data.
In my opinion, have a look at Scray and some Headless Browers.
Check the flowing links for more information
https://scrapy.org/
https://github.com/puppeteer/puppeteer
https://github.com/pyppeteer/pyppeteer

How can I pass data from one page to another in PHP and Javascript without from?

How can I pass data from one page to another page in PHP using Javascript without from?
In my blog have a post comment with email Id
and this is routing using foreach loop
problem occur when get email id and comment
how can i do this? plz help
you can make use of client side cookie for this. one page you create cookie and on second page read that cookie.
I guess that what you dislike with forms is the page reloading on the client side.
If that is the case then you can use ajax requests (maybe with the help of a framework like jQuery, or pure javascript with the xmlHTTPRequest()).
Alternatively you can use cookies, but it's not what they really are for.
If you don't mind the page reloading, you can also use HTTP GET requests with javascript :
location.assign("http://www.my_site.com/index.php?param1=value1&param2=value2");
You can also store data in Web storage if the data doesn't necessarily need to be processed in PHP.
You will need to have a backup system in cookies though for the older browsers that do not support his.

Twitter like new tweet count notification in ASP.Net

I have very limited knowledge in jQuery. I need to develop a page which should show the count of new message posted. In twitter and stackoverflow websites, I have seen a div which shows the count of new tweet/questions posted and while clicking on it, the newer ones are shown on the top. Below added are the sample images:
Please suggest whether it can be attained using jQuery or Ajax.
Thanks
Those examples look like push rather than pull behaviors. By this I mean that the server is saying to the page 'hey there is a new tweet in this tag' rather than the page asking 'is there any new tweet? No not yet? OK, I'll ask again in 5sec'.
Since you are on ASP.NET, you can easily push notifications from server to client by using the good SignalR library.
You still have to detect on the server that there are new 'things' and send a message (with signalR) to the matching clients. And also handle the message on the client and show a piece of UI.
As you are using ASP.NET, you can use an UpdatePanel to help handle making the call and updating your content. Note that the UpdatePanel uses AJAX, and can be set to automatically update on a specified time interval.
What I would do, if I were you, is use the UpdatePanel to call a method that makes a request to the Twitter API and grabs all of the new tweets that you have not already grabbed. Then count the number of tweets returned and, if that number is greater than zero, I would display the "X tweets with new activity", or whatever counter message you are looking to show.
If you are not strong with jQuery, this may be the best solution for you, as you could get away with using the UpdatePanel and a Repeater to render out your tweets, and update the ones displayed when clicking a button/link/etc, with or without postback (whichever is your preference for this implementation).
Important Side-Note
Note that Twitter API v1.1 requires you to use oAuth Tokens, which should not be included in AJAX calls. You should only be using server-side code to make requests to the Twitter API, and, thus, this solution is likely to be the best for you, as you can write your request code in the code-behind (thus keeping your Twitter keys and tokens safe), and call it using the UpdatePanel.
Update
I am not usually one to promote my own libraries on Stack, but if you need help with making the request to Twitter's API using oAuth, take a look at my C# library for Twitter requests. The documentation includes instructions for setting up oAuth access on Twitter and is very verbose in helping you make calls with the library. It also includes MSDN-style documentation for the library, itself, an example request, and full IntelliSense for all classes, methods, and properties. If nothing else, it should help you set up your requests. If you have any trouble with it, let me know and I can help you out.
You need to retrieve the new messages using a $.ajax call which you repeat every few minutes or so using setTimeout. But for that ajax call to work you have to have some sort of API endpoint you can retrieve the data from.
This is not just something you can build by dropping in a jQuery plugin somewhere and be done with it. You need to have knowledge about Javascript, jQuery and your specific API before you can do anything. Try checking out the jQuery basic tutoorial.
You can create a WCF service to get latest messages which you can call using setTimeout to update your message div in real time using Ajax or you can use SignalR to add real time functionality.

Rails pushing content dynamically after finishing request

At the moment, im building a Website with Ruby on Rails.
Problem:
My Website is using different foreign API's for getting Data, for example the Amazon Product Advertising API. If i load e.g. 10 objects at once, it tooks to mutch time.
Its possible to load each object particular? (If one request finished push it with javascript on the page, or something like that) The user should be able to read the first objects while the rest of the content is loading in the background.
simple example:
list.each do |object|
result << AmazonRequest.getItem(object)
[And now push the changed result list to the view]
end
Is this possible? If yes, how?
Thanks :)
I don't really know RoR, but if you do not need to have all the different API results on the server before sending them out (which seems to be the case), you could just make multiple ajax requests and display content from the different APIs independently.

Is auto post back in ASP.net and AJAX are the same?

Is auto post back in ASP.net and AJAX are the same??? I want to send data to server and store that data in XML file without refreshing the page. I dont want to use ajax.. If there is any other way to do this with plain javascript then do let me know... thanks in advance...
Is auto post back in ASP.net and AJAX are the same???
Not from a users perspective. When doing a postback, the user will see his entire page getting refreshed. When using AJAX, the user will not see his page get refreshed
I want to send data to server and store that data in XML file without
refreshing the page. I dont want to use ajax.. If there is any other way
to do this with plain javascript
If you want to interact with the server without refreshing the page, you have to use AJAX.
Note: You may be confusing AJAX with the various AJAX controls / libraries like AjaxControlToolKit etc. If that is the case, then you can definitely use AJAX without using any of the libraries / controls. That is done by using the XMLHTTPRequest and XMLHTTPResponse objects directly via Javascript. However, that in itself is AJAX. Sample code of how to do it can be seen in this page
So, atleast as far as i know, you need to use AJAX to go to the server without appearing to the user that your page has gotten refreshed.
as InSane said PostBack is quite different in AJAX and asp.net. AJAX mostly use Partial postback using XMLHTTPRequest Objects while full page postback sends complete Page's data to server resulting in complete page recycle.
For Your second question.. if you don't want to postback and still want to send some data to server there is only one way to do this by AJAX. AJAX in javascript is quite obscure i'll prefer using some javascript library like JQuery. Here is a link that shows how to call WebMethod on an ASPX page from JQuery.
http://encosia.com/2008/05/29/using-jquery-to-directly-call-aspnet-ajax-page-methods/
Hope this will help.
Regards.

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