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What is Ruby?

Ruby is a high-level, interpreted and object-oriented programming language. It is a dynamic open-source language that has a great community behind it. Ruby was designed for simplicity and productivity. It encourages writing human first and computer second software code. It was created by Yukihiro Matsumoto in Japan in 1995.

What is Rails?

Rails is a development framework written in Ruby for building web applications. It was created as the foundation of Basecamp application and then released as an open-source software in 2004. Rails offers many in-built standard features and functionalities, which makes it a suitable option for MVP prototyping and development.

It was created by David Heinemeier Hasson popularly known as DHH. It is one of the most influential and popular tools for building web applications. It is used by some of the favourite sites like Airbnb, Github, Shopify, etc.

In this Ruby on Rails tutorial for beginners, you will learn Ruby on Rails basics like:

Why Rails?

Here are pros/ benefits of using Rails:

Rails is packaged as a Ruby gem, and you can use it to build a variety of applications.

It allows you to build regular web applications, e-commerce applications, content management system, and more.

Rails is a full-stack framework that includes everything you need to create a database-driven web application, using the Model-View-Controller pattern.

This means that all the layers are built to work seamlessly together with less code. It requires fewer lines of code than other frameworks.

How to Download and Install Ruby on Windows

The installation process will depend on your operating system. You will go through installing Ruby on Windows, Mac, and Linux.

All you have to do is run the downloaded installer.

Check the first two checkboxes to make running Ruby scripts easier.

This step installs MSYS2, a building platform that features a package manager for easy Installation of packages on Windows.

Press Enter to install all the components as they are all required to have a smooth Ruby on Rails development environment to work with on Windows.

Installing Rails

You should have Ruby installed from the previous section, and now you are going to install Rails. You can install Rails using a package from RailsInstaller, but the problem with this is that you don’t get the latest version of the required packages.

If you have already have the latest Ruby and a baseline set of required RubyGems and extensions installed. All you need do now is run the following command at the command prompt to get Rails on your system: ‘gem install rails.’

It is a more common and preferred approach to developing on Windows. Rails community uses a Windows Subsystem for Linux that provides a GNU/Linux environment with command-line tools, utilities, and common applications directly on Windows.

Installing Ruby on Mac

Your Mac already has Ruby pre-installed on it. However, the pre-installed version might be old, and so you will need to install a new/latest version.

The easiest way to do this is by using a package manager such as Homebrew. You might first need to install Homebrew by running the command below at the Terminal.

This will display a warning and ask you to enter your password. Enter your Mac password (you won’t see the characters as you type). Just press ‘Enter’ when you are done typing your password. Then run this simple Homebrew command to install Ruby on your Mac.

brew install ruby

And also run this command:

To set this Ruby installation as the default Ruby to run on your system and not the pre-installed Ruby.

To confirm the Installation was successful, you can run the following at the Terminal

ruby --version

this will print the Ruby version number you have installed. The output will look something like

ruby 2.6.0p0 (2023-12-25 revision 66547) [x86_64-darwin18] Installing Ruby on Ubuntu (Linux)

The easiest way to get Ruby installed on your Ubuntu system is through the apt package manager. You need to run the following commands at the Terminal to install the latest Ruby from Ubuntu repositories.

sudo apt update – This will update the default Ubuntu repositories

sudo apt install ruby-full – It will download and installs the latest Ruby

To confirm the Installation was successful, you can run the following ‘ruby –version,’ this will print the Ruby version you have installed.

Installing Rails on Ubuntu (Linux)

You should follow the steps below to successfully install Rails on your Linux machine.

Step 1) Update your computer gem manager by running ‘gem update –system’ at the Terminal or command prompt.

Step 2) Run ‘gem install rails’ to install the latest version of Rails on your computer.

Step 3) You should install bundler gem for easy Rails application gem dependency management. Run ‘gem install bundler’ to get it.

Two principles of Rails

Rails follow basic software design principles and encourage you to use those principles too.

The two most common are:

Don’t Repeat Yourself (DRY) – this makes you write concise, consistent, and maintainable code.

Convention over Configuration – Rails is pre-configured to use sensible defaults that fit most common usage. This makes your application development fast, and you also have less code to maintain.

Rails – Project File Structures

With Rails now installed on your system lets create a Rails application! We will learn Ruby on Rails examples and how to create a Todo list application in this Ruby on Rails tutorial. Run the following command ‘rails new todo_app’ in your Terminal to create the application.

This command creates a directory named ‘todo_app’ in the current directory with the basic folder structure of a Rails web application, as shown in the Figure below:

You will go through the main directories in this Ruby on Rails example.

app – This directory groups using different subdirectories for the UI/layout (views and helpers), the controller (controllers files) and the models (business/application logic).

app/controllers – This directory stores controller files used by Rails to handle requests from the client.

app/assets – It contains static files, which is a need for the application’s front-end grouped into folders based on their type – JavaScript files, images, and stylesheets.

app/helpers – This subdirectory contains helper functions that make your application model, view, and controller logic focused, small and uncluttered.

app/models – This contains files

that model your application’s database. The model classes make working with the database very easy.

app/views – This hold template/layout files the user of your application interacts with. The templates are a combination of HTML and data from the database.

bin – It contains Rails scripts that starts your application. It can also include other scripts that you use to set up and upgrade the application.

Config – This holds configuration files – database.yml, chúng tôi chúng tôi etc. that your application needs to run.

DB – This directory contains files/scripts that are used to manage your application database.

lib – This directory contains an extended module for your application.

log – This contains log files – server.log, chúng tôi chúng tôi and chúng tôi etc., that are used for debugging or monitoring your application.

public – This directory contains static files and compiled assets, such as HTML files, Javascript files, images, and stylesheets.

test – This directory holds test files you write to test your application functionality.

tmp – This directory contains temporary files like cache and pid files.

vendor – This directory contains third-party libraries.

Gemfile – This file specifies what your basic gem requirements are to run your web application. You can group the gems into development, test or production and Rails will know when to include each gem.

Gemfile.lock – Unlike the Gemfile that explicitly lists the gems you want in your application, chúng tôi additionally contains other gems that those you list in the Gemfile depends on that are then automatically installed to satisfy the dependencies.

Readme.md – You use this file to share essential detail about your application, such as what the app does, how to go about installing and run the application.

Rakefile – This file contains various rake tasks definitions, which helps in automating everyday administration tasks of your application.

config.ru – This is a Rack configuration file that provides an interface to the webserver to start your application.

Change directory to the ‘todo_app’ directory Rails generated and run ‘rails server’ to start the application. Type localhost:3000 in the address bar of your web browser, you should see the Figure below if all went well.

This is the default homepage of your application, and you will change this in the later section of this Ruby on Rails tutorial. You can stop the server by pressing ‘Ctrl-C’.

Rails – Generate commands

The Rails generate command makes use of templates to create a whole lot of useful things in your application. You can use these generators to save a lot of time.

It helps by writing boilerplate code, code that is necessary for your web application to work. You can run ‘rails generate’ by itself at the command prompt or Terminal to see a list of available generators as shown below:

You can also run ‘rails generate “command”‘ to see a description of what the command does. It offers convenient options that can be run with the command and usage example. The Figure below shows the output of running‘ rails generate controller’:

You will use the rails generate scaffold command to automatically create the model, view, and controller for the todo list application you are building. Run‘ rails generate scaffold todo_list title:string description: text’ in your Terminal (check you are still in the todo_app directory).

This will create a full CRUD (Create, read, update, and delete) web interface for the TodoLists table.

Rails – routing

The Rails routing system, rails router, handles all incoming requests to your web application. It does this by examining the URL of the incoming requests and then maps each request to the controller action responsible for handling it, using special syntax specified in the routes file (config/routes.rb).

The routes file helps in controlling every URL aspect of your web application. Rails by default use a RESTful design based on the REST architectural style, that provides a mapping between HTTP verbs and requests (URLs) to controller actions.

The routes file was generated when you ran ‘rails new’ in an earlier section of this tutorial. Continuing with the Todo application that you are building, run the following‘ rails db:migrate’ (you will get to know what this does shortly)

In your command line, make sure you are still at the root of the application (the todo_app directory).

This is the Todo lists view that the scaffold command generated and it is controlled by the TodoListsController’s index action.

Rails was able to map the various requests (URLs) to the corresponding TodoListsController’s action using the route definition in config/routes.rb.

If you take a peek at this file, you see a single line ‘resources: todo_lists’, is Rails default way of writing restful routes. This single line creates seven routes all mapping to the TodoLists controller.

By convention, each controller’s action also maps to a specific CRUD (Create, Read, Update, and Delete) operation in the database.

You can run ‘rake routes’ in your command line to see the various routes available in your application. The Figure below shows the output of running ‘rails routes’ in your command line/terminal.

Rails – views

The View layer is one of the components of the MVC paradigm and is responsible for generating HTML response for each request to your application. Rails by default use ERB (Embedded Ruby) which is a powerful templating system for Ruby.

ERB makes writing templates easy and maintainable by combining plain text with Ruby code for variable substitution and flow control. An ERB template has .html, .erb or .erb extension.

You will mostly use a combination of two tag markers only, each of which causes the embedded code to be processed and handled in a particular way.

Each controller in your Rails application has a corresponding subdirectory in app/views, and each action/method in a controller has a corresponding .html and .erb file in this directory.

Take a look at app/views of the todo app you are building. You will find a subdirectory named ‘todo_lists’ inside this subdirectory chúng tôi files with names corresponding to the actions/methods in the TodoLists controller.

Rails – ActiveRecord, Active Record Pattern, and ORM

ActiveRecord is the Ruby implementation of the Active Record pattern, which is a simple pattern where a class represents a table, and an instance of the class represents a row in that class.

ActiveRecord is popularly referred to as an ORM (Object Relational Mapping), a technique that allows you to manage your database using a language you’re most comfortable with. It is database agnostic thus you can easily switch between databases (for example SQLite, MySQL, PostgreSQL, SQL Server, Oracle, etc.). This suite more for your application requirement with the same code/logic.

So, if you want to get an array containing a listing of all the todo lists in your application, so, instead of writing code to initiate a connection to the database, then doing some sort of SQL SELECT query, and converting those results into an array.

For that, you just need to type ‘TodoList.all’ and Active Record gives you the array filled with TodoList objects that you can play with as you like.

All you need do is set up the right configuration in config/database.yml, and Active Record will work out all the differences between the various database system. So when you switch from one to the other, you don’t have to think about it.

You focus on writing code for your application, and Active Record will think about the low-level details of connecting you to your database. Active Record makes use of naming conventions to create the mapping between models and database tables.

Rails pluralize your model class names to find the corresponding database table. So, for a class TodoList, ActiveRecord will create a database table called TodoLists.

Rails – Migrations

Rails migration is simply a script that you use to edit your application database. It is used to set up or change your database and avoids manually writing SQL code to do that.

It uses Ruby to define changes to database schema and makes it possible to use version control to keep your database synchronized.

Rails Migrations use a Ruby Domain Specific Language (DSL). This acts as an abstraction and makes it possible to use or change your database engine based on your requirements.

They can be shared with anyone working on the application and can also be rolled back to undo any changes to the database. This is a high safety mechanism as you don’t have to bother about doing permanent damage to your database.

Rails – ActiveRecord Associations

A connection between two ActiveRecord models is known as an association. Association makes it much easier to perform operations on the different records in your code. It can be divided into four categories: –

One to One: – This indicates that a record contains precisely one instance of another model. A good example is user profile. A user has only one profile. It uses has _one keyword.

One to Many: – This is the most common association, and it indicates that one model has zero or more instances of another model. Your use has a _many keyword to denote this association.

Many to Many: – This association is a bit more complicated, and ActiveRecord provides two ways to handle it. Using the has_and_belongs_to_many and has_many, which gives you access to the relation that is defined in a separate table.

Rails – ActiveRecord Validations

Validation helps to ensure that you have correct data because working with wrong data is an awful thing and could cost you your money and business.

Validation also provides an extra layer of security for your application against malicious users from gaining access to information in your database. Rails offer you a nice API of validation helpers in ActiveRecord to keep your database clean, secure, and free of errors.

ActiveRecord validations run on model objects before saving to the database, making them more reliable and also best practice to follow in building your application.

The following ActiveRecord methods evoke validations when used or called on model objects – create, create!, save, save!, update, and update!. The ones with a bang (create!, save! and update!) raise an exception if a record is invalid while thothen’t’tt’t’t.

The most common ActiveRecord validation helpers at your disposal are:-

Presence:– This checks that the field is not empty.

uniqueness: ensures unique value for a field, e.g., username

Length:- To enforce a limit on character length of a field

You can also create your custom validation by using the validate method and passing it the name of the custom validation method.

You can check the model’s error object to find out why a validation. Hopefully, you have some ideas to make your application more constrained and more secured to only allow secure data into your database.

Rails – ActionController

The Rails controller is the center of your web application. It facilitates and coordinates the communication between the user, the models, and the views.

Your controller classes inherit from the ApplicationController, that contains code that can be run in all other controllers and it inherits from ActionController class.

The controller provides the following to your application:

It routes external requests to internal actions

It manages to cache, giving performance boosts to your application

It manages helper methods that extend view templates capabilities. It also manages user sessions, giving them a smooth experience using your app.

Rails – Configurations

You can configure the various components such as initializers, assets, generators, middlewares, etc. By using your Rails application initializers and configuration files in the config directory. Files like config/application.rb, config/environments/development.rb and config/environments/test.rb etc. You can also have custom settings configure for your application.

Rails – Debugging

As you build out your application, there will come a time you will need/have to debug your code. Rails make this easy using the byebug gem. You can start a debugging session by putting the ‘byebeg’ keyword anywhere in your application code.

This will temporarily stop execution at that point. The byebug gem gives you several commands to use. The most useful ones are:

next: command that enables you to go to the next line of code, skipping all methods invoked by the execution of the current line.

step: this is similar to ‘next’ command but will make you step into each invoked.

break: this stops the code execution.

continue continues execution code.

There are other debugging gems available such as ‘pry’, and they all provide similar functionalities but slightly different syntax. Debugging gems should not be used in production as this pose’s risks to your application and bad experience to your application users.

There are log files that you can inspect for errors in production and handle them. Also, you should follow a TDD (Test-driven development) approach when developing your application to ensure everything works well before deploying to production.

Summary:

Ruby is a pure object-oriented programming language

Ruby has an elegant syntax that is both easy to read and write.

Rails is a development framework, written in Ruby, for building web applications

The installation process will depend on your operating system.

Rails is packaged as a Ruby gem, and you can use it to build a variety of applications.

You will create a Todo list application in this tutorial, run the followincomm’n’n’ ‘rails netoda’p’p’p’ in youR Terminal to create the application.

The Rails generate command makes use of templates to create a whole lot of useful things in your application.

The Rails routing system, rails router helps you to handles all incoming requests to your web application.

The View layer is one of the components of the MVC paradigm and is responsible for generating HTML response for each request to your application.

ActiveRecord is the Ruby implementation of the Active Record pattern.

Rails migration is simply a script that you use to edit your application database.

A connection between two ActiveRecord models is known as an association.

Validation helps to ensure that you have correct data because working with wrong data is an awful thing and could cost you your money and business.

The Rails controller helps you to facilitates and coordinates the communication between the user, the models, and the views.

Rail helps you to configure the various components such as initializers, assets, generators, middlewares, etc.

You're reading Ruby On Rails Tutorial For Beginners With Project & Example

Ruby On Rails 2.1

Ruby on Rails 2.1 – Routes System

Rails parses the URL to determine the controller, action, and parameters for the request. With Rails routing, parts of the URL can specify additional parameters, and the entire routing process is under your control. Routing rules work the same on any web server.

The config/routes.rb file is at the heart of the Rails routing system. This file contains rules that try to match the URL path of a request and determine where to direct that request. The rules are tested in the order they are defined in the file. The first rule to match a request’s URL path determines the fate of that request.

The routing system actually does two things −

It maps requests to action methods inside the controllers.

It writes URLs for you for use as arguments to methods like link_to, redirect_to, and form_tag.

Thus, the routing system knows how to turn a visitor’s request URL into a controller/action sequence. It also knows how to manufacture URL strings based on your specifications.

Consider the following route installed by Rails when you generate your application −

map.connect ':controller/:action/:id'

This route states that it expects requests to consist of a :controller followed by an :action that in turn is fed some :id.

}

Thus the default routing (if you don’t modify the routing rules) is −

The following code block will set up book as the default controller if no other is specified. It means visiting ‘/’ would invoke the book controller.

end

You can also define a default action if no action is specified in the given URL −

map.connect ':controller/:action/:id', end

Now, you can all edit methods inside the book controller to edit book with ID as 20 as follows −

http://localhost:3000/2 Route Priority

Routes have priority defined by the order of appearance of the routes in the chúng tôi file. The priority goes from top to bottom.

The last route in that file is at the lowest priority and will be applied last. If no route matches, 404 is returned.

Modifying the Default Route

You can change the default route as per your requirement. In the following example, we are going to interchange controller and action as follows −

# Install the default route as the lowest priority. map.connect ':action/:controller/:id'

Now, to call action from the given controller, you would have to write your URL as follows −

http://localhost:3000/action/controller/id

It’s not particularly logical to put action and controller in such sequence. The original default (the default default) route is better and recommended.

The Ante-Default Route

The ‘ante-default’ route looks as follows −

map.connect ':controller/:action/:id.:format'

The .:format at the end matches a literal dot and a wildcard “format” value after the id field. That means it will match, for example, a URL like this −

http://localhost:3000/book/show/3.xml

Here, inside the controller action, your params[:format] will be set to xml.

The Empty Route

Here are some examples of fairly common empty route rules −

Here is the explanation of the above rules −

Rails 2.0 introduces a mapper method named root which becomes the proper way to define the empty route for a Rails application, like this −

Defining the empty route gives people something to look at when they connect to your site with nothing but the domain name.

Named Routes

As you continue developing your application, you will probably have a few links that you use throughout your application. For example, you will probably often be putting a link back to the main listings page. Instead of having to add the following line throughout your application, you can instead create a named route that enables you to link to a shorthand version of that link −

You can define named routes as follows. Here instead of using connect, you are using a unique name that you can define. In this case, the route is called home. The rest of the route looks similar to the others you have created.

Now, you can use this in the controllers or views as follows −

Here, instead of listing the :controller and :action to which you will be linking, you are instead putting the name of the route followed by _url. Your user shouldn’t notice any difference. Named routing is merely a convenience for the Rails developer to save some typing. The above case can be written without the named route as follows −

Pretty URLs

Routes can generate pretty URLs. For example −

map.connect 'articles/:year/:month/:day', # Using the route above, the url below maps to:

To obtain more detail on Routes, please go through ActionController::Routing.

How To Use Windows 10 Pc – Basic Tutorial & Tips For Beginners

This guide is meant for users who have just started using Windows 10 OS and will also help seniors who may be new to the PC. It will show you how to use Windows 10 – right from how to sign-in to how to shut down your PC. Windows 10 is undoubtedly a bit different than the earlier versions of Windows, especially for absolute beginners. When I say the absolute beginners, I mean the new PC users and the grannies and grandpas who may have just started using the computer. In this post, I will share some basic tips for using Windows 10.

Read: How to set up & configure a new Windows computer.

How to use Windows 10 PC

You should always ensure that your laptop battery is charged properly so that you do not run out of power at the wrong time. If you are using a desktop, make sure you use a battery backup as well.

1] How to sign in to your computer

On the right side, you see some icons, hover over them with your mouse cursor and you will get and an idea of what they are there for.

Further reading: Different ways to sign into Windows 10.

2] Desktop and Start Menu

Once you are signed in, you will be at the Desktop, which is the basic overview of your PC. You can open all your files, folders and applications from here. You will see some icons and the Taskbar at the bottom of the screen that has some more icons and the Start button in the extreme left corner.

Play around a bit to get the hang of it.

Further reading: How to customize the Start Menu.

3] Windows File Explorer

This is the file manager of your computer using which you can access all your files, data, pictures and folders. To open your files and folders in the PC, you need to go via File Explorer.

$Ruby Listed On Coinsbit Exchange

The $RUBY token has been listed and made available for trade on the Coinsbit cryptocurrency exchange just yesterday. Coinsbit, one of Europe’s largest and award-winning crypto exchanges, listed the native $RUBY token to its 1.5 million registered platform users on the 24th of March.

Coinsbit dropped the news of the two RUBY trading pairs available through its social media accounts, a normal practice of the centralized exchange, with some further trading competitions and bounty events rumored to be in the works. The Coinsbit exchange offering represents the second-largest since Ruby Play Network began its string of listings on March 15th. chúng tôi offers 2 trading pairs for $RUBY. Users can buy & sell $RUBY and trade with BNB or USDT pairings.

Ruby is now available to trade on Coinsbit with BNB and USDT pairings open

More on the Coinsbit launch and early indications

Since the listing went live on Coinsbit, about 24 hours ago according to the current time, $RUBY has increased 5% in price. Multiple exchanges and staking platforms are now offering various offers including staking, farming, and $RUBY trading across a variety of markets. The 5% increase does come as a bit of a surprise, certainly being different from the normal trend seen in cryptocurrency.

Typically in these cases the chart reflects the opposite, with many traders known to “sell the news” as projects list crypto tokens on exchanges such as Coinsbit for the very first time. The return of games like Spin2Win and RubySweeper, both currently being reconditioned, could play a part in the continued usage and utility of RUBY, with games that users can play daily and use their RUBY outside of merely buying and selling – seemingly within the next phase of plans for the Ruby Play Network as a whole.

Other Ruby Play Network news

Further gaming propositions have already been mentioned from the Ruby Play Network, as the platform focus has been clearly said to be expansion and growth of the gaming partnerships and offerings on RPN now and consistently in the future. Additionally, a transition is being implemented to more consumer-focused messaging, with the emphasis being given to bringing attention to the gaming and other opportunities present on the Ruby Play Network and with its partners.

Blockchain gaming partner – Strawberry – has provided liquidity to multiple platforms for $RUBY live staking to begin. The XPortal offers staking by Strawberry, with other staking options also being offered on ApeSwap Jungle Farms and ACY Finance respectively – through this cross-purpose partnership.

Next steps for Ruby Play Network

The transition of RUBY tokens to multisig wallets for automation, greater security and transparency, has already begun. The move to the smart protocol-coded wallets allows for tokens allocated to adoption mining and vested tokens to be scheduled and viewed publicly on the blockchain ledger.

The continued growth and collaboration with Strawberry look to be a key motivation for the platform. Strawberry Sweeps social casino pays out in BTC, USDT and Ethereum, with players also being rewarded in $RUBY in exchange for time in play. The Strawberry social casino is due to be rolled out to further regions and markets in the near future, providing some further gaming utility to wider Ruby Play Network users.

The adoption mining model has seen an increase in usage on the network, with traffic to the platform up 50 times compared to 4 months ago. How the platform leverages and engages with this user base is where the success will lie going forward. Keep up-to-date with all things $RUBY via the Twitter, Telegram and Discord channels.

Brendan Brown

[email protected]

Php Ajax Tutorial With Example

What is Ajax?

AJAX full form is Asynchronous JavaScript & XML. It is a technology that reduces the interactions between the server and client. It does this by updating only part of a web page rather than the whole chúng tôi asynchronous interactions are initiated by chúng tôi purpose of AJAX is to exchange small amounts of data with server without page refresh.

JavaScript is a client side scripting language. It is executed on the client side by the web browsers that support JavaScript.JavaScript code only works in browsers that have JavaScript enabled.

XML is the acronym for Extensible Markup Language. It is used to encode messages in both human and machine readable formats. It’s like HTML but allows you to create your custom tags. For more details on XML, see the article on XML

Why use AJAX?

It allows developing rich interactive web applications just like desktop applications.

Validation can be performed done as the user fills in a form without submitting it. This can be achieved using auto completion. The words that the user types in are submitted to the server for processing. The server responds with keywords that match what the user entered.

It can be used to populate a dropdown box depending on the value of another dropdown box

Data can be retrieved from the server and only a certain part of a page updated without loading the whole page. This is very useful for web page parts that load things like

Tweets

Commens

Users visiting the site etc.

How to Create an PHP Ajax application

We will create a simple application that allows users to search for popular PHP MVC frameworks.

Our application will have a text box that users will type in the names of the framework.

We will then use mvc AJAX to search for a match then display the framework’s complete name just below the search form.

Step 1) Creating the index page

chúng tôi

HERE,

“onkeyup=”showName(this.value)”” executes the JavaScript function showName everytime a key is typed in the textbox.

This feature is called auto complete

Step 2) Creating the frameworks page

chúng tôi

<?php $frameworks = array("CodeIgniter","Zend Framework","Cake PHP","Kohana") ; $name = $_GET["name"]; $match = ""; for ($i = 0; $i < count($frameworks); $i++) { if (strtolower($name) == strtolower(substr($frameworks[$i], 0, strlen($name)))) { if ($match == "") { $match = $frameworks[$i]; } else { $match = $match . " , " . $frameworks[$i]; } } } } echo ($match == "") ? 'no match found' : $match; Step 3) Creating the JS script

auto_complete.js

function showName(str){ if (str.length == 0){ document.getElementById("txtName").innerHTML=""; return; } if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari } else {// code for IE6, IE5 } } } }

HERE,

“if (str.length == 0)” check the length of the string. If it is 0, then the rest of the script is not executed.

“if (window.XMLHttpRequest)…” Internet Explorer versions 5 and 6 use ActiveXObject for AJAX implementation. Other versions and browsers such as Chrome, FireFox use XMLHttpRequest. This code will ensure that our application works in both IE 5 & 6 and other high versions of IE and browsers.

Step 4) Testing our PHP Ajax application

Type the letter C in the text box You will get the following results.

The above example demonstrates the concept of AJAX and how it can help us create rich interaction applications.

Summary

AJAX is the acronym for Asynchronous JavaScript and XML

AJAX is a technology used to create rich interaction applications that reduce the interactions between the client and the server by updating only parts of the web page.

Internet Explorer version 5 and 6 use ActiveXObject to implement AJAX operations.

Internet explorer version 7 and above and browsers Chrome, Firefox, Opera, and Safari use XMLHttpRequest.

Requirements Analysis Techniques With Example: Complete Tutorial

As a Business Analyst, requirement analysis is the most important part of your Job. It will help you determining the actual needs of stakeholders. At the same time, enable you to communicate with the stakeholders in a language they understand (like charts, models, flow-charts,) instead of complex text.

A requirement analysis has a

Specific Goal

Specific Input

Specific Output

Uses resources

Has a number of activities to be performed in some order

May affect more than one organization unit

Creates value of some kind for the customer

Monday

Learn More

On Monday’s Website

Time Tracking

Yes

Drag & Drop

Yes

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Requirement Analysis Techniques

Requirement analysis techniques are mainly used to map the business workflow so that you can analyze, understand and make required changes to that workflow or process.

There are various requirement analyzing techniques that can be used as per the software development process like

Business process modeling notation (BPMN)

BPMN (Business Process Modeling & Notation) is a graphical representation of your business process using simple objects, which helps the organization to communicate in a standard manner. Various objects used in BPMN includes

Flow objects

Connecting objects

Swim lanes

Artifacts.

A well design BPMN model should be able to give the detail about the activities carried out during the process like,

Who is performing these activities?

What data elements are required for these activities?

The biggest benefit of using BPMN is that it is easier to share, and most modeling tools support BPMN.

UML (Unified Modeling Language)

UML is a modelling standard primarily used for specification, development, visualization and documenting of software system. To capture important business process and artifacts UML provides objects like

State

Object

Activity

Class diagram

There are 14 UML diagrams that help with modelling like the use case diagram, interaction diagram, class diagram, component diagram, sequence diagram, etc. UML models are important in the IT segment as it becomes the medium of communication between all stakeholders. A UML-based business model can be a direct input to a requirements tool. A UML diagram can be of two type’s Behavioral model and Structural model. A behavioral model tries to give information about what the system do while a structural model will give what is the system consist of.

Flow chart technique

Data flow diagram

Data flow diagrams show how data is processed by a system in terms of inputs and outputs. Components of data flow diagram includes

Process

Flow

Store

Terminator

A logical data flow diagram shows system’s activities while a physical data flow diagram shows a system’s infrastructure. A data flow diagram can be designed early in the requirement elicitation process of the analysis phase within the SDLC (System Development Life Cycle) to define the project scope. For easy analyzing a data flow diagram can be drilled down into its sub-processes known as “levelled DFD”.

Role Activity Diagrams- (RAD)

Role activity diagram is similar to flowchart type notation. In Role Activity Diagram, role instances are process participants, which has start and end state. RAD requires a deep knowledge of process or organization to identify roles. The components of RAD includes

Activities

External events

States

Roles group activities together into units of responsibility, according to the set of responsibility they are carrying out. An activity can be carried out in isolation with a role, or it may require coordination with activities in other roles.

External events are the points at which state changes occur.

States are useful to map activities of a role as it progresses from state to state. When a particular state is reached, it indicates that a certain goal has been achieved.

RAD is helpful in supporting communication as it is easy to read and present a detailed view of the process and permitting activities in parallel.

Gantt Charts

A Gantt chart is a graphical representation of a schedule that helps to coordinate, plan and track specific tasks in a project. It represents the total time span of the object, broken down into increments. A Gantt chart represents the list of all task to be performed on the vertical axis while, on the horizontal axis, it list the estimate activity duration or the name of the person allocated to the activity. One chart can demonstrate many activities.

IDEF (Integrated Definition for Function Modeling)

IDEF or Integrated Definition for Function Modeling is a common name referred to classes of enterprise modeling languages. It is used for modeling activities necessary to support system analysis, design or integration. There are about 16 methods for IDEF, the most useful versions of IDEF are IDEF3 and IDEF0.

Colored Petri Nets (CPN)

CPN or colored petri nets are graphically oriented language for specification, verification, design and simulation of systems. Colored Petri Nets is a combination of graphics and text. Its main components are Places, Transitions, and Arcs.

Petri nets objects have specific inscription like for

Places: It has inscription like .Name, .Color Set, .Initial marking etc. While

Transition : lt has inscription like .Name (for identification) and .Guard (Boolean expression consist of some of the variables)

Arcs: It has inscription like .Arc. When the arc expression is assessed, it yields multi-set of token colors.

Workflow Technique

Workflow technique is a visual diagram that represent one or more business processes to clarify understanding of the process or to make process improvement recommendations. Just like other diagrams like flowcharting, UML activity and process map, the workflow technique is the oldest and popular technique. It is even used by BA for taking notes during requirements elicitation. The process comprises of four stages

Information Gathering

Workflow Modeling

Business process Modeling

Implementation, Verification & Execution

Object oriented methods

Object-oriented modeling method uses object oriented paradigm and modeling language for designing a system. It emphasis on finding and describing the object in the problem domain. The purpose of object oriented method is

To help characterizing the system

To know what are the different relevant objects

How do they relate to each other

How to specify or model a problem to create effective design

To analyze requirements and their implications

This method is applicable to the system which has dynamic requirements (changes frequently). It is a process of deriving use cases, activity flow, and events flow for the system. Object oriented analysis can be done through textual needs, communication with system stakeholder and vision document.

The object has a state, and state changes are represented by behavior. So, when the object receives a message, state changes through behavior.

Gap Analysis

Gap Analysis is the technique used to determine the difference between the proposed state and current state for any business and its functionalities. It answers questions like what is the current state of the project? Where do we want to be? etc. Various stages of Gap Analysis include

Review System

Development Requirements

Comparison

Implications

Recommendations

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