str_split() function used to convert a string into array.
str_split()
<?php
$str = “Hello”;
$arr = str_split($str);
print_r($arr);
?>
OUTPUT : Array ( [0] => H [1] => e [2] => l [3] => l [4] => o )
PHP Questions and Answers
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.
What is the use of array_slice() in PHP ?
array_slice() is used to extract a slice of an array. It returns the sequence of elements from the array as specified by the parameters.
str_split()
<?php
$languageArray = array(“php”, “java”, “c++”, “pearl”, “python”);
$languages = array_slice($languageArray,0 ,2);
print_r($languages);
?>
OUTPUT: Array ( [0] => php [1] => java )
What things we keep in mind to write an optimize MySQL Query ?
1 : Instead of using SELECT * we should specify the columns name like SELECT column1,column2 which have use in our script.
2 : We should use indexing of tables for which we are writing queries.
3 : Try to use the LIMIT if we need only a specific number of rows.
How can we get all the properties of browser in PHP
We can get the browser properties in PHP by :
echo $_SERVER[‘HTTP_USER_AGENT’] . “\n\n”;
OR
$browser = get_browser(null, true);
print_r($browser);
How to read the contents of a file in PHP ?
Read the contents of a file in PHP
<?php
$fileName = “file01.txt”;
//fopen() function is used to open a file in php
$file = fopen($fileName,”r”) or exit(“Unable to open the file!”) ;
While(!feof($file)) // feof()checks the end of file in php
{
echo fgets($file); // fgets() read a fileline by line in php
}
fclose($file); // fclose() used to close a file in php
?>
How can we change the time zones using PHP ?
We can change the time zones by using date_default_timezone_set() function
eg : date_default_timezone_set(‘America/Los_Angeles’);
How can we destroy a session in PHP ?
We can destroy session by using session_destroy(); .
session_destroy()
<?php
session_destroy() ;
?>
What is PHP filter ?
PHP filter is used to validate the data coming from different sources like the user’s input.
It is important part of a web application to test, validate the data coming from insecure sources.
We have different functions to validate the data:
filter_var();
filter_var_array();
filter input();
filter_input_array();
filter_var()
<?php
email_a = ‘user@website.com’;
if (filter_var($email_a, FILTER_VALIDATE_EMAIL)) {
echo “This (email_a) email address is considered valid.”;
//reported as valid
}
?>
What is the use of error_reporting(-1); ?
error_reporting(-1) will Report all PHP errors but error_reporting(0) will turn off all error reporting
How we can create a zip file using PHP ?
For this case we can use ZipArchive class. PHP’s ZIP class provides all the functionality we need.
Please refer this link : http://www.php.net/manual/en/zip.examples.php