jQuery string manipulation performance vs. PHP - php

Im building a custom jquery modal box that loads an external html template file that contains variables that need to be replaced. For instance: [user-name]
I know I have 2 options for modifying the template file:
use find and replace in jquery
process the template server side and
simply send the result to jquery
From a user performance stand point, which would be faster?

From a user point of view it would be faster to use jquery . you don't loose time by sending and reciveing data from the server

Not having any details about why you're asking, I would say that it probably doesn't matter.

Related

Add several specification without saving first

I'm working on a editing tool (type of a simple CMS) in PHP/MySQL for a product catalog. I have search the Internet for a solution but I don't even know what to search for. So now my hope is on you guys.
I have a form where you can put all kinds of data like part.no, description an so on. All of this data is saved into a MySql table (items). I also have a table with predefined specifications.
What I want to do, and that I can't find a solution for, is to have a dropdown meny (or similar) and a add button to add a row for each related specifications without saving the whole form each time. I want to save first when all specifications is selected.
So, can I use PHP for this or do I need jQuery/Javascript or similar? I know it's possible, have seen it in OpenCart :-)
I hope someone understands my question. It's hard to explane i a language I'm not fully manage.
Regards
Client-side vs Server-side
Javascript: This sits in the user's browser. So anything you want to move in the user's browser will be done with JavaScript. This is "client-side"
PHP: This site on the server, so takes inpute from the user's browser and gives back a response (generally HTML, but can also be JSON or XML which is read by Javascript.). This is "server-side".
Libraries
jQuery: This is a set of functions written for Javascript to make it easier. So it runs in the user's browser and makes it easier for you to write bits that move on the screen.
You get similar libraries that help you write PHP (commonly called "frameworks") and there are many others for javascript as well.
Where to start
Write your HTML page as you want it to look. Keep it simple for the first time.
Then write some javascript (possibly using jQuery) to move the menu. Google "jquery menu dropdown" or similar and you'll find a solution you cna customise.
Then write some PHP that gives you the HTML you wrote in '1'.
Then decide what's going to happen when you click on a link in the HTML, and repeat the process (write HTML, incorporate Javascript to make it move, write PHP to give HTML)
Then work out which bits of the HTML are common or structured and should come from a database.
Without writing it for you (in which case you'll never learn) best to start one bit at a time and build as your knowledge grows. Bucket loads of examples on the web when youreach a particular problem you need to solve.
After comment "[how to] make it possible to select and add single/multiple specifications (from another table) without saving the whole form each time a specs is added":
Growing with AJAX
What you are asking is AJAX - this is where you get Javascript to talk to the server, and for javascript to move bits on the page based on the results. jQuery is probably the easiest (and probably has best documentation / examples for the ajax, as well as moving the DOM).
Basically: you have an "event" that you trap in JavaScript, example
/// Using jQuery to trap a button click
$().ready( function() {
$("#ButtonID").click( function(e) {
e.preventDefault();
alert('Button Clicked');
});
});
Then you build in an AJAX call inside that event (also check out get or post as the syntax is easier, you just get less control). The AJAX wil send a request to your PHP server, and you can get PHP to return HTML which you can replace/insert using the DOM manipulation functions linked below (e.g. before, html etc) or, when you get more advanced, you'll send back JSON which is a data structure you cna more easily manipulate in JavaScript to stipulate what actions are required.
As above, without actually writing it for you, the best place to start is to read the docs and have a go. Google "jquery AJAX PHP table example" or similar and you'll find an example somewhere.

Change elements upon button press?

I am getting started with HTML and PHP. Doing alright, I understand the syntax and everything. But... what I know is simply how to build page elements that may interact with other .php files in my site. But what if I want to interact with other elements in the same page?
This is what I'm trying to achieve:
I got some text and a button. I want to press the button, and that will cause my text to become a textbox which I can edit, and afterwards press the button again to convert the textbox back to plain text.
That is what I don't quite get: interacting with other elements to change their attributes/values, seems to be little documentation about that, or I am looking in the wrong place. If that is the case, can someone point me to the correct learning source?
Thanks.
You need javascript for that.... There are loads of examples online and everywhere:
http://www.w3schools.com/js/tryit.asp?filename=tryjs_dom
You are looking at the wrong place as you can't do that with PHP. Changing elements on the client side will involve JavaScript. There are a lot of ways to change elements with JS and to get a quick start I'd suggest you take a look at jQuery, a JS library that will make it easy for you to access and change elements.
What you're looking for is client side interaction. Javascript is the ticket for this and you'll have to include a tag in the head of your html doc.
Look up javascript on w3schools.com and then learn jQuery which is a great implementation of key javascript principles with a lot of extra features like animation and client/server side interaction.
You are moving into the realms of Dynamic HTML. The easiest way I have found to manipulate elements within an HTML page is to use JQuery.
PHP is a predominantly a server scripting language and has very little impact on browser-centric behavior. HTML is a markup language, but with few exceptions isn't dynamic. You want to look into content/browser scripting languages - depending on your medium, the two more popular for the time being are Javascript and Actionscript.
PHP does not allow you to change your HTML dynamically. As the other people mentioned, you need Javascript for that.
What you could do is reload the page on button click and change a session variable (for example) to decide wether the text is displayed as a textbox or just text.

Displaying database content - PHP vs Javascript

I am (mostly) a front-end developer working on a prototype with a backend guy on a site. The basics of it would require a user login area, as well as a search form that would search and return results from a database table.
He is doing the backend logic with Java and PostgreSQL. He proposes to return a JSON format to me upon a query. This means I will have to take the data from the JSON string and populate/create the HTML markup. I can do this with either Javascript, or PHP. It seems to be that PHP would be a no brainer as I don't need to create HTML markup with Javascript/jQuery and also all the data populated by the server already, reducing the load on the client side, but this means as a "front-end" person I am also writing PHP.
And regarding loading all server data onto a page with Javascript, is this standard practice? Or should it only be used on AJAX?
Should the backend guy be generating the markup as well? What's the best way of separating this frontend and backend work? THanks!
If you are using PHP, you are a backend-guy, too.
If the markup is generated by the server, than you would usually not write an AJAX-application, because the markup is generated by the server.
In fact if you want to write a ajax-application, you have to manipulte the DOM with Javascript. Use jQuery or something like that to do this.
Seperating frontend and backend is done by creating an Interface, a contract which will separate the UI from the Backend-Logic. In your case the contract is the format of your JSON Data.
A good compromise would be to do either:
Option 1
A small PHP script server-side which formats the restults into a table with appropriate Ids/similar to allow javascript to add classes for styling. This entire table could be returned via an AJAX call and placed within a placeholder div on the page.
Option 2
The server returns simple JSON to the front-end, the front-end uses whatever mechanism it sees fit to build the appropriate HTML
The first one is a little cleaner to code - The generation of the HTML is seperated from the styling, but it's an extra hop (the PHP) and is slightly inflexible - the JS can modify the table as appropriate but it's limited by the html PHP sends.
The second is slightly more verbose to code but completely flexible.
I send the data from the server to the browser in JSON all the time, format on the browser with templates of one form or another. I would rather work with arrays in Javascript as the array methods like map and filter make it much easier.

SQLITE php javascript? auto refresh without entire page refresh

I have a simple php code which prints data from a SQLite database.
Basically $query ="Select A from B".
This all works fine. & when the sqlite db updates, i can refresh the page & the new data displays.
Want i am aiming to achieve is to refresh this data automatically every 5-10 seconds without having to reload the entire page.
I am also trying to avoid using iframes as there is about 20 of these on the page all displaying different data.
This has been driving me mad the last few days, Does anyone know of a way to do so?
My thought have been javascript, jquery or AJAX?
Other than that can you get sqlite data with javascript alone, without php?
& then implement something like the below on the element only? without the page reloading??
setTimeout("location.reload();",5000);
Thank you in advance.
You can do it using setInterval(), passing a jQuery ajax command and the time.
Or take a look at this jQuery plugin http://plugins.jquery.com/project/ekko
I'd recommend using jQuery as it's easy to do this sort of thing with the built in ajax function. Download jQuery and embed in your page or embed via a CDN.
1.) create a PHP file that outputs the content you want to "update" every few minutes. No headers/footers, etc.
2.) Put the content you want to refresh in a div with some specific id.
3.) Check out the simple example for using setInterval and ajax/load on this page.
Ajax is what you need.
Two options that I use quite a bit, both with plusses and minuses:
Jquery, easy to learn, quick to deploy, and very configurable
XAJAX -- AJAX for PHP. It's not the best thing out there, but if you're scared of Javascript, this allows you to do AJAX from PHP Functions, which can be easier for PHP guys to understand.
In essence, output your code to a specific DIV, then use AJAX to update that div with data it queries from the DB.

How can I save content from another website to my database?

I want to upload dynamically content from a soccer live score website to my database.
I also want to do this daily, from a single page on that website (the soccer matches for that day).
If you can help me only with the connection and retrieval of data from that webpage, I will manage the rest.
website: http://soccerstand.com/
language: php/java - mysql
Thank you !
You can use php's file function to get the data. You just pass it a URL and it returns the content as an array of lines from the file. You can also use file_get_contents to get the content as one big string.
Ethical questions about scraping other site's data aside:
With php you can do an "open" call on a website as long as you're setup corectly. See this page for more details on that and examples: http://www.php.net/manual/en/wrappers.http.php
From there you have the content of the web page and it's a matter of breaking it up. Off the top of my head, I'd use regular expressions or an HTML parser to break apart the HTML, and then loop through the child elements and parse the data into your database calls to save the data.
There are a lot of resources for parsing HTML on the web and it's simply a matter of choosing the one that will work best for you.
Keep in mind you'll need to monitor the site for changes, because if they change elements, or their classes/ids you might need to change your parsing structure as well.
Using curl you will get the content of the page, then using regex you will get what you want.
There is an easy way: http://www.jonasjohn.de/lab/htmlsql.htm

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