Question: What is PEAR in php?
PEAR means PHP Extension and Application Repository.
PEAR is a framework and distribution system for reusable PHP components. PEAR can be installed by bringing an automated wizard.
Following are main purpose of PEAR
A structured opensource library .
Distribution and package maintenance.
The PHP Foundation Classes (PFC)
The PHP Extension Community Library (PECL)
Question: How can we repair a MySQL table?
We can repair the MySQL with following 3 queries. Each have its own feature.
REPAIR TABLE tablename REPAIR TABLE tablename QUICK REPAIR TABLE tablename EXTENDED
Question: What Is a Persistent Cookie?
A persistent cookie is a cookie which is stored in a cookie file permanently on the browser.
A persistent cookie can be used for tracking long-term information.
Persistent cookies are less secure.
Question: How to create persistent cookie in php?
Cookies will only persistent for as long as you have set them.
setcookie( "cookieName", 'cookieValue', strtotime( '+1 year' ) ); //set for 1 year
Question: What is meant by urlencode and urldecode?
urlencode() returns the URL encoded version of the given string.
It convert special characters into % signs followed by two hex digits.
urldecode() returns the Decodes any %## encoding in the given string. Plus symbols ('+') are decoded to a space character.
Question: How To Get the Uploaded File Information in PHP Global variables?
We are all data in $_FILES variable and are following
$_FILES[$fieldName]['name'] - The Original file name on the browser system.
$_FILES[$fieldName]['type'] – The file type determined by the browser.
$_FILES[$fieldName]['size'] – The Number of bytes of the file content.
$_FILES[$fieldName]['tmp_name'] – The temporary filename of the file in which the uploaded file was stored on the server.
$_FILES[$fieldName]['error'] – The error code associated with this file upload.
Question: How can I execute a PHP script using command line?
php c:/wamp/www/myfile.php
Question: Are objects passed by value OR by reference?
Everything is passed by value.
Question: How do you call a constructor of a parent class from child class?
parent::constructor();
Question: Can we use include ("abc.php") two or more times?
Yes, we can include mutiple times.
Question: What is the difference between the functions unlink and unset?
unlink() deletes the given file from the file system.
unset() makes a variable undefined from memory
Question: What are the different functions in sorting an array?
Sort() arsort() asort() ksort() natsort() natcasesort() rsort() usort() array_multisort() uksort().
Question: How can we get the browser properties using PHP?
$_SERVER['HTTP_USER_AGENT']
Question: How can I configure PHP to show error at runtime?
error_reporting(E_ALL)
Question: How do I turn off PHP Notices?
Add following code in top of php script.
error_reporting(0);
Question: What is T_PAAMAYIM_NEKUDOTAYIM?
T_PAAMAYIM_NEKUDOTAYIM the scope resolution operator (double colon)
::
Qustion: What is output of following program?
function doSomething( &$arg )
{
$return = $arg;
$arg += 1;
return $return;
}
$a = 3;
$b = doSomething( $a );
echo $a;
echo '\n';
echo $b;
Question: How to protect your website from SQL injection attack?
use mysql_real_escape_string() function.
Question: How to protect your website from CSRF (Cross-Site Request Forgery) attack?
Add a token on every important request to secure important operations
Question: How to protech your website from XSS (Cross-Site Scripting) attack?
use php function htmlentities()
Question: what is the list of sensible functions?
exec(), passthru(), system(), popen(), eval(), preg_replace()
Question: What is output of following?
$a = 012; echo $a / 4;
