PHP is an important part of the web world, and every web developer should have the basic knowledge in PHP. Common PHP questions, which should help you become a best PHP developer.
It returns the absolute pathname of the currently executing script.
Note:
If a script is executed with the CLI(Command-line interface), as a relative path, such as file.php or ../file.php, $_SERVER[‘SCRIPT_FILENAME’] will contain the relative path specified by the user.
ob_start() will turn output buffering on. While output buffering is active no output is sent from the script (other than headers), instead the output is stored in an internal buffer.
It is using to print a data in the webpage, Example: , This code print the text in the webpage of a website.
Include a file using “include() ” or “require()” function with file path as its parameter.
Example : include ‘page.php’; or require ‘page.php’;
In PHP, the array() function is using to create an array.
1. $fruits = array(‘apple’, ‘orange’, ‘pineapple’);
2. $cars =array();
$cars[0]=”Maruthi”;
$cars[1]=”Benz”;
$cars[2]=”Figo”;
3. $ages = array(“Kiran”=>”25″,”Vipin”=>”28″,”Sanooj”=>”27”);
In PHP, print is not actually a real function (it is a language construct) so you are not required to use parentheses with its argument list.
Example :
print(“Hello World”);
print ‘Hello World’;
It helps to checks if a value exists in an array.
mysql_connect() Open a Connection to the MySQL Server.
Syntax : mysql_connect(servername,username,password);
// Check connection
if (mysqli_connect_errno())
{
echo “Failed to connect to MySQL: ” . mysqli_connect_error();
}
mysql_select_db() is using to select a MySQL database.
// Check connection
if (!$link) {
die(‘Not connected : ‘ . mysql_error());
}
// Select database
$db_selected = mysql_select_db(‘database_name’, $link);
if (!$db_selected) {
die (‘Not Selected database’ . mysql_error());
}
Short for PHP Extension and Application Repository, PEAR is a framework and distribution system for reusable PHP components. It is a structured library of open-source code for PHP users. It following a system for code distribution and package maintenance and a standard style for code written in PHP.
Please refer this URL : http://pear.php.net/manual/en/standards.php