PHP Questions & Answers – Strings and Regular Expressions – 2

PHP Questions and Answers for focuses on “Strings and Regular Expressions – 2”.

Q 1. How many functions does PHP offer for searching and modifying strings using Perl-compatible regular expressions.
A. 7
B. 8
C. 9
D. 10

Show Answer

Answer:-B. 8

Explanation

The functions are preg_filter(), preg_grep(), preg_match(), preg_match_all(), preg_quote(), preg_replace(), preg_replace_callback(), and preg_split().

Q 2. What will be the output of the following PHP code?

<?php
$foods = array(“pasta”, “steak”, “fish”, “potatoes”);
$food = preg_grep(“/^s/”, $foods);
print_r($food);
?>
A. Array ( [0] => pasta [1] => steak [2] => fish [3] => potatoes )
B. Array ( [3] => potatoes )
C. Array ( [1] => steak )
D. Array ( [0] => potatoes )

Show Answer

Answer:-C. Array ( [1] => steak )

Explanation

This function is used to search an array for foods beginning with s.

Q 3. Say we have two compare two strings which of the following function/functions can you use?

i) strcmp()
ii) strcasecmp()
iii) strspn()
iv) strcspn()
A. i) and ii)
B. iii) and iv)
C. only i)
D. i), ii), iii) and iv)

Show Answer

Answer:-D. i), ii), iii) and iv)

Explanation

All of the functions mentioned above can be used to compare strings in some or the other way.

Q 4. Which one of the following functions will convert a string to all uppercase?
A. strtoupper()
B. uppercase()
C. str_uppercase()
D. struppercase()

Show Answer

Answer:-A. strtoupper()

Explanation

Its prototype follows string strtoupper(string str).

Q 5. What will be the output of the following PHP code?

<?php
$title = “O’malley wins the heavyweight championship!”;
echo ucwords($title);
?>
A. O’Malley Wins The Heavyweight Championship!
B. O’malley Wins The Heavyweight Championship!
C. O’Malley wins the heavyweight championship!
D. o’malley wins the heavyweight championship!

Show Answer

Answer:-A. O’Malley Wins The Heavyweight Championship!

Explanation

The ucwords() function capitalizes the first letter of each word in a string. Its prototype follows: string ucwords(string str).

Q 6. What will be the output of the following PHP code?

<?php
echo str_pad(“Salad”, 5).” is good.”;
?>
A. SaladSaladSaladSaladSalad is good
B. is good SaladSaladSaladSaladSalad
C. is good  Salad
D. Salad  is good

Show Answer

Answer:-D. Salad  is good

Explanation

The str_pad() function pads a string with a specified number of characters.

Q 7. Which one of the following functions can be used to concatenate array elements to form a single delimited string?
A. explode()
B. implode()
C. concat()
D. concatenate()

Show Answer

Answer:-B. implode()

Q 8. Which one of the following functions finds the last occurrence of a string, returning its numerical position?
A. strlastpos()
B. strpos()
C. strlast()
D. strrpos()

Show Answer

Answer:-D. strrpos()

Q 9. What will be the output of the following PHP code?

<?php
$author = “nachiketh@example.com”;
$author = str_replace(“a”,”@”,$author);
echo “Contact the author of this article at $author.”;
?>
A. Contact the author of this article at nachiketh@ex@mple.com
B. Cont@ct the @uthor of this @rticle @t n@chiketh@ex@mple.com
C. Contact the author of this article at n@chiketh@ex@mple.com
D. Error

Show Answer

Answer:-C. Contact the author of this article at n@chiketh@ex@mple.com

Explanation

The str_replace() function case sensitively replaces all instances of a string with another.

Q 10. What will be the output of the following PHP code?

<?php
$url = “nachiketh@example.com”;
echo ltrim(strstr($url, “@”),”@”);
?>
A. nachiketh@example.com
B. nachiketh
C. nachiketh@
D. example.com

Show Answer

Answer:-D. example.com

Explanation

The strstr() function returns the remainder of a string beginning with the first occurrence of a predefined string.