String replace functions in PHP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the PHP function str_replace() do?

It replaces all occurrences of a search string with a replacement string within another string.

beginner

How do you replace the word 'cat' with 'dog' in the string 'The cat is cute' using PHP?

Use str_replace('cat', 'dog', 'The cat is cute') which returns 'The dog is cute'.

intermediate

What is the difference between str_replace() and str_ireplace() in PHP?

str_replace() is case-sensitive, while str_ireplace() ignores case when replacing strings.

intermediate

Can str_replace() replace multiple different strings at once?

Yes, by passing arrays for the search and replace parameters, it can replace multiple strings in one call.

intermediate

What does the optional fourth parameter of str_replace() do?

It stores the number of replacements made as an integer.

Which PHP function replaces all occurrences of a string, ignoring case?

A str_ireplace()

B str_replace()

C substr_replace()

D strtolower()

str_ireplace() replaces strings without considering case differences.

What will str_replace('a', 'b', 'apple') return?

A bpple

B apple

C bppleapple

D bppleappleb

All 'a' characters are replaced with 'b', so 'apple' becomes 'bpple'.

How can you replace multiple different words in one call using str_replace()?

A By using regular expressions

B By calling <code>str_replace()</code> multiple times

C By passing arrays for search and replace parameters

D By using <code>str_ireplace()</code>

Passing arrays lets you replace multiple strings in one function call.

What does the optional fourth parameter of str_replace() store?

A The replaced string

B Length of the original string

C Boolean success/failure

D Number of replacements made

It stores the count of how many replacements were done.

Which function would you use to replace a substring at a specific position in PHP?

A str_replace()

B substr_replace()

C str_ireplace()

D strpos()

substr_replace() replaces part of a string at a given position.

Explain how to replace multiple different words in a string using PHP string replace functions.

Think about how arrays can be used as inputs.

Describe the difference between str_replace() and str_ireplace().

Focus on how they treat uppercase and lowercase letters.