Escape sequences in strings in PHP - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of escape sequences in double-quoted strings

What is the output of the following PHP code?

PHP

<?php
echo "Line1\nLine2\tTabbed";
?>

A Line1\nLine2\tTabbed

B Line1 Line2 Tabbed

C

Line1
Line2	Tabbed

D Line1\nLine2 Tabbed

💡 Hint

Remember that double-quoted strings interpret escape sequences like \n and \t.

In PHP, double-quoted strings interpret escape sequences. \n creates a new line, and \t adds a tab space. So the output shows Line1, then a new line, then Line2 followed by a tab and 'Tabbed'.

❓ Predict Output

intermediate

Escape sequences in single-quoted strings

What will this PHP code output?

PHP

<?php
echo 'Line1\nLine2\tTabbed';
?>

A

Line1
Line2	Tabbed

B Line1\nLine2\tTabbed

C Line1 Line2 Tabbed

D Line1\nLine2 Tabbed

💡 Hint

Single-quoted strings do not interpret most escape sequences except \' and \\.

In PHP, single-quoted strings treat most escape sequences as literal characters. So \n and \t are printed as two characters \ and n or t, not as newline or tab.

❓ Predict Output

advanced

Using variable interpolation with escape sequences

What is the output of this PHP code?

PHP

<?php
$name = "Anna";
echo "Hello, $name\nWelcome!";
?>

A

Hello, $name
Welcome!

B Hello, $name\nWelcome!

C Hello, Anna\nWelcome!

D

Hello, Anna
Welcome!

💡 Hint

Double-quoted strings allow variable interpolation and escape sequences.

In double-quoted strings, PHP replaces $name with its value 'Anna' and interprets \n as a newline. So the output is Hello, Anna followed by a new line and Welcome!

❓ Predict Output

advanced

Escape sequences with curly braces in variable interpolation

What does this PHP code output?

PHP

<?php
$fruit = "apple";
echo "I have an {$fruit}s.";
?>

A I have an apples.

B I have an apple s.

C I have an {$fruit}s.

D I have an $fruits.

💡 Hint

Curly braces help PHP know where the variable name ends in strings.

Using {$fruit}s tells PHP to replace $fruit with 'apple' and then add 's' after it, resulting in 'apples'.

🧠 Conceptual

expert

Understanding complex escape sequences in strings

Which option correctly describes the output of this PHP code snippet?

PHP

<?php
echo "Path: C:\\Users\\John\nNew Line";
?>

A

Path: C:\Users\John
New Line

B Path: C:\\Users\\John\nNew Line

C

Path: C:UsersJohn
New Line

D Path: C:\Users\John\nNew Line

💡 Hint

Remember that \\ in double quotes prints a single backslash, and \n prints a newline.

In PHP, double-quoted strings interpret \\ as a single literal backslash. So C:\\Users\\John becomes C:\Users\John, and \n becomes a newline. The output is two lines: 'Path: C:\Users\John' and 'New Line'.