PHP Interview Questions and Answers

There are differences between php5 and php7.

• PHP 5 is released 28 August 2014 but PHP 7 released on 3 December 2015
• It is one of the advantages of the new PHP 7 is the compelling improvement of performance.
• Improved Error Handling
• Supports 64-bit windows systems
• Anonymous Class
• New Operators

On our website you will find industry's best PHP interview questions for freshers.

1. array_combine(): It is used to creates a new array by using the key of one array as keys and using the value of another array as values.

Example :

$array1 = array('key1', 'key2', 'key3'); $array2 = array(('umesh', 'sonu', 'deepak'); $new_array = array_combine($array1, $array2); print_r($new_array);

OUTPUT : Array([key1]  => umesh[key2]    => sonu[key2]    =>deepak)

2. array_merge(): It merges one or more than one array such that the value of one array appended at the end of the first array. If the arrays have the same strings key, then the next value overrides the previous value for that key.

Example :

$array1 = array("one" => "java","two" => "sql"); $array2 = array("one" => "php","three" => "html","four"=>"Me"); $result = array_merge($array1, $array2); print_r($result); Array ( [one] => php [two] => sql [three] => html [four] => Me )

We can use the count() or size() function to get the number of elements or values in an array in PHP.

With the help of strip_tags(), we can remove HTML tags from data in PHP.

The strip_tags() function strips a string from HTML, XML, and PHP tags.

strip_tags(string,allow)

The first parameter is required. It specifies the string to check.

The second parameter is optional. It specifies allowable tags. Mention tags will not be removed

$$var is known as reference variable where $var is a normal variable.

$actual_link = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http") . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

The error_reporting() function defines which errors are reported.We can modify these errors in php.ini. You can use these given function directly in php file.

error_reporting(E_ALL);
ini_set('display_errors', '1');

It suppresses error messages. It’s not a good habit to use @ because it can cause massive debugging headaches because it will even contain critical errors

It is a PHP library and a command line tool that helps us to send files and also download data over HTTP and FTP. It also supports proxies, and you can transfer data over SSL connections.

Exception handling was introduced in PHP 5 as a new way for the execution of code and what exceptions to make in code in case of a specific error.

There are various keywords of exception handling in PHP like:

Try: This try block consists of the code which could potentially throw an exception. All the code in this try block is executed unless and until an exception is thrown.

Throw: This throw keyword is used to alert the user of a PHP exception occurrence. The runtime will then use the catch statement to handle the exception.

Catch: This keyword is called only when there is an exception in the try block. The code of catch must be such that the exception thrown is handled efficiently.

Finally: This keyword is used in PHP versions 5.5 and above where the code runs only after the try and catch blocks have been executed. The final keyword is useful for situations where a database needs to be closed regardless of the occurrence of an exception and whether it was handled or not.

Note: From the vast number of PHP interview questions, answering this will help you to align yourself as an expert in the subject. This is a very tricky question that often makes developers nervous.