10 Essential PHP String Manipulation Functions with Examples

In PHP development, strings are fundamental, and mastering key string functions can greatly improve code efficiency.

Part 1: Substring and Concatenation

$string = "Hello World";

$result = substr($string, 6, 5); // outputs "World"

substr(string $string, int $start[, int $length]) extracts a portion of a string starting at a given position.

$string = "Hello World";

$result = str_replace("World", "PHP", $string); // outputs "Hello PHP"

str_replace(mixed $search, mixed $replace, mixed $subject[, int &$count]) replaces occurrences of a search string with a replacement.

$array = array("Hello", "PHP", "World");

$result = implode(" ", $array); // outputs "Hello PHP World"

implode(string $glue, array $pieces) joins array elements into a single string using a specified separator.

Part 2: Search and Checks

$string = "Hello PHP World";

$result = strpos($string, "PHP"); // outputs 6

strpos(string $haystack, mixed $needle[, int $offset = 0]) returns the position of the first occurrence of a needle. $result = str_contains($string, "PHP"); // outputs 1 (true) str_contains(string $haystack, mixed $needle) checks if a string contains a given substring (PHP 8.0+).

$result = str_starts_with($string, "Hello"); // outputs 1 (true)

str_starts_with(string $haystack, mixed $needle) determines whether a string starts with a given prefix (PHP 8.0+).

$result = str_ends_with($string, "World"); // outputs 1 (true)

str_ends_with(string $haystack, mixed $needle) determines whether a string ends with a given suffix (PHP 8.0+).

Part 3: Split and Formatting

$string = "Hello,PHP,World";

$result = explode(",", $string); // outputs array('Hello','PHP','World')

explode(string $delimiter, string $string[, int $limit = PHP_INT_MAX]) splits a string into an array by a delimiter.

$string = "  Hello World  ";

$result = trim($string); // outputs "Hello World"

trim(string $string[, string $characters = " \t\n\r\0\x0B"]) removes whitespace or specified characters from both ends of a string.

$name = "Alice";

$age = 25;

$result = sprintf("My name is %s and I am %d years old.", $name, $age); // outputs "My name is Alice and I am 25 years old."

sprintf(string $format, mixed ...$args) returns a formatted string according to the given format.

By applying these ten essential functions—substr, str_replace, implode, strpos, str_contains, str_starts_with, str_ends_with, explode, trim, and sprintf—developers can manipulate strings more efficiently, leading to cleaner and more maintainable PHP code.