Zend Framework Interview Questions and Answers
Freshers / Beginner level questions & answers
Ques 1. What is a framework?
In software development, a framework is a defined support structure in which another software project can be organized and developed.
=> An abstract design
=> Set of common functionality
=> Developed for a particular domain
Ques 2. Why should we use framework?
Framework is a structured system
=> Source codes become more manageable
=> Easy to extend features
=> Rapid application development
Ques 3. Configuration in Zend Framework, application.ini file?
Configuration can be done in application.ini file in Zend framework. This file in the path application/configs/application.ini.
Ques 4. Checking whether form posted or not in Zend framework?
if($this->getRequest()->isPost()){ echo "Form posted"; }
Ques 5. Does Zend Framework support PHP 4?
No. Zend Framework was built to use all of the sophisticated object oriented features of PHP 5 and take advantage of significant performance and security enhancements.
Ques 6. What is Bootstrapping?
Many PHP applications funnel server requests into a single (or few) PHP source file that sets up the environment and configuration for the application, manages sessions and caching, and invokes the dispatcher for their MVC framework. They can do more, but their main job is to take care of the consistent needs of every page of a web application.
In our Blueprint for PHP Applications, we will have a core bootstrapper that receives all dynamic requests for an application and applies a template for application behavior that we can later extend. It will allow us to later customize the functionality for each unique application.
Ques 7. What is zend engine?
Zend Engine is used internally by PHP as a complier and runtime engine. PHP Scripts are loaded into memory and compiled into Zend opcodes.
Ques 8. What is zend engine in PHP?
Zend engine is like a virtual machine and is an open source, and is known for its role in automating the web using PHP. Zend is named after its developers Zeev and Aandi. Its reliability, performance and extensibility has a significant role in increasing the PHP’s popularity. The Zend Engine II is the heart of PHP 5. It is an open source project and freely available under BSD style license.
Ques 9. what is routing and how it's work?
Zend_Controller_Router_Rewrite is the standard framework router. Routing is the process of taking a URI endpoint (that part of the URI which comes after the base URL) and decomposing it into parameters to determine which module, controller, and action of that controller should receive the request. This values of the module, controller, action and other parameters are packaged into a Zend_Controller_Request_Http object which is then processed by Zend_Controller_Dispatcher_Standard. Routing occurs only once: when the request is initially received and before the first controller is dispatched.
Zend_Controller_Router_Rewrite is designed to allow for mod_rewrite-like functionality using pure PHP structures. It is very loosely based on Ruby on Rails routing and does not require any prior knowledge of webserver URL rewriting. It is designed to work with a single Apache mod_rewrite rule.
Ques 10. What are Plugins in zend framework?
• Triggered by front controller events
• Events bookend each major process of the front controller
• Allow automating actions that apply globally
Creating Plugins:
• Extend Zend_Controller_Plugin_Abstract
• Extend one or more of the event methods
Ques 11. Zend_Cache provides a generic way to cache any data.
Caching in Zend Framework is operated by frontends while cache records are stored through backend adapters (File, Sqlite,Memcache...) through a flexible system of IDs and tags. Using those, it is easy to delete specific types of records afterwards (for example: "delete all cache records marked with a given tag").
The core of the module (Zend_Cache_Core) is generic, flexible and configurable. Yet, for your specific needs there are cache frontends that extend Zend_Cache_Core for convenience: Output, File, Function and Class.
Ques 12. What is MVC?
=> Model-View-Controller development pattern.
=> MVC is a software approach that separates application logic from presentation.
Ques 13. What is Front Controller?
It used Front Controller pattern. zend also use singleton pattern.
=> routeStartup: This function is called before Zend_Controller_Front calls on the router to evaluate the request.
=> routeShutdown: This function is called after the router finishes routing the request.
=> dispatchLoopStartup: This is called before Zend_Controller_Front enters its dispatch loop.
=> preDispatch: called before an action is dispatched by the dispatcher.
=> postDispatch: is called after an action is dispatched by the dispatcher.
Intermediate / 1 to 5 years experienced level questions & answers
Ques 14. Difference between Zend_Registry and Zend_Session?
The basic difference between these objects is the ‘scope’ in which they are valid:
a) Zend_Registry : request scope
b) Zend_Session : session scope
a) Zend_Registry is used to store objects/values for the current request. In short, anything that you commit to Registry in index.php can be accessed from other controllers/actions (because EVERY request is first routed to the index.php bootstrapper via the .htaccess file). Config parameters and db parameters are generally prepped for global use using the Zend_Registry object.
b) Zend_Session actually uses PHP sessions. Data stored using Zend_Session can be accessed in different/all pages. So, if you want to create a variable named ‘UserRole’ in the /auth/login script and want it to be accessible in /auth/redirect, you would use Zend_Session.
Ques 15. When do we need to disable layout?
At the time of calling AJAX to fetch we need to disable layout.
$this->_helper->layout()->disableLayout();
$this->_helper->viewRenderer->setNoRender(true);
Ques 16. Where is the model in ZF’s MVC implementation?
The model component can vary dramatically in responsibilities and data store from one MVC application to the next.
Ques 17. How to call two different views from same action?
Example1:
Public function indexAction() {
If(condition)
$this->render(‘yourview.phtml’);
Else
Index.phtml;
Example2:
Public function indexAction() {
}
Now in your index.phtml you can have this statement to call other view
$this->action(‘action name’,’controller name’,’module name’,array(‘parameter name’=>’parameter value’));
Ques 18. How to include css from controller and view in zend.
From within a view file: $this->headLink()->appendStylesheet(‘filename.css’);
From within a controller: $this->view->headLink()->appendStylesheet(‘filename.css’);
And then somewhere in your layout you need to echo out your headLink object:
headLink();?>
Ques 19. How do you protect your site from sql injection in zend when using select query?
You have to quote the strings,
$this->getAdapter ()->quote (
$select->where ( ”
OR (If you are using the question mark after equal to sign)
$select->where ( ”
Ques 20. Features of MVC in Zend Framework?
=> Declare custom routing rules
Not limited to “controller/action/param” format
=> Optional Controller Plugins, Action Helpers, and View Helpers
ErrorHandler plugin handles exceptions, 404 errors, etc.
FlashMessenger, Redirector, ViewRenderer helpers
Output common HTML elements in views
=> Extensible interfaces
Write your own plugins and helpers
Ques 21. Why can't Zend_Form render my File element without errors?
The file element needs a special file decorator, which is added by default. When you set your own decorators for file elements, you delete the default decorators.
For example:
$element->setDecorators(array(
array('ViewHelper'),
array('Errors')
));
You should use a File decorator instead of the ViewHelper for the file element, like so:
$element->setDecorators(array(
array('File'),
array('Errors')
));
Ques 22. How can I customize the appearance of forms generated by Zend_Form?
You're probably looking for decorators. All forms and form elements in Zend_Form use decorators to render their output.
Ques 23. Why does the Zend Framework project have a CLA at all?
The CLA protects all users including individuals, small and medium businesses, and large corporations. By having a CLA in place, we mitigate the risk that companies who claim intellectual property infringement may demand royalties or fees from users of Zend Framework, whether individuals or companies. This is especially important for companies basing their business or products on Zend Framework. The Zend Framework CLA helps to ensure that code and other IP in Zend Framework remains free.
Ques 24. Should I sign an individual CLA or a corporate CLA?
If you are contributing code as an individual- and not as part of your job at a company- you should sign the individual CLA. If you are contributing code as part of your responsibilities as an employee at a company, you should submit a corporate CLA with the names of all co-workers that you foresee contributing to the project.
Most helpful rated by users:
- What is a framework?
- Why should we use framework?
- Configuration in Zend Framework, application.ini file?
- Checking whether form posted or not in Zend framework?
- Does Zend Framework support PHP 4?