TrimFormatter

The TrimFormatter removes characters from the edges of strings with configurable characters and side selection, fully supporting UTF-8 Unicode characters.

Usage

Basic Usage

use Respect\StringFormatter\TrimFormatter;

$formatter = new TrimFormatter();

echo $formatter->format('  hello world  ');
// Outputs: "hello world"

Trim Specific Side

use Respect\StringFormatter\TrimFormatter;

$formatter = new TrimFormatter('left');

echo $formatter->format('  hello  ');
// Outputs: "hello  "

$formatterRight = new TrimFormatter('right');

echo $formatterRight->format('  hello  ');
// Outputs: "  hello"

Custom Characters

use Respect\StringFormatter\TrimFormatter;

$formatter = new TrimFormatter('both', '-._');

echo $formatter->format('---hello---');
// Outputs: "hello"

echo $formatter->format('._hello_._');
// Outputs: "hello"

Unicode Characters

use Respect\StringFormatter\TrimFormatter;

// CJK full-width spaces are trimmed by default
$formatter = new TrimFormatter();

echo $formatter->format('　hello世界　');
// Outputs: "hello世界"

// Trim emoji with custom characters
$formatterEmoji = new TrimFormatter('both', '😊');

echo $formatterEmoji->format('😊hello😊');
// Outputs: "hello"

API

TrimFormatter::__construct

• __construct(string $side = "both", string|null $characters = null)

Creates a new trim formatter instance.

Parameters:

• $side: Which side(s) to trim: "left", "right", or "both" (default: "both")
• $characters: The characters to trim from the string edges, or null for default Unicode whitespace (default: null)

Throws: InvalidFormatterException when $side is not "left", "right", or "both"

format

• format(string $input): string

Removes characters from the specified side(s) of the input string.

Parameters:

• $input: The string to trim

Returns: The trimmed string

Examples

Side	Characters	Input	Output	Description
"both"	null	" hello "	"hello"	Trim default whitespace both sides
"left"	null	" hello "	"hello "	Trim default whitespace left only
"right"	null	" hello "	" hello"	Trim default whitespace right only
"both"	"-"	"---hello---"	"hello"	Trim hyphens from both sides
"both"	"-._"	"-._hello_.-"	"hello"	Trim multiple custom characters
"left"	":"	":::hello:::"	"hello:::"	Trim colons from left only
"both"	null	"　hello"	"hello"	CJK space trimmed by default
"both"	"😊"	"😊hello😊"	"hello"	Trim emoji with custom characters

Notes

• Uses PHP's mb_trim, mb_ltrim, and mb_rtrim functions for multibyte-safe trimming
• Fully UTF-8 aware - handles all Unicode scripts including CJK, emoji, and complex characters
• Empty strings return empty strings
• If the characters string is empty or contains no characters present in the input, the string is returned unchanged
• Trimming operations are character-oriented, not byte-oriented

Default Characters

When no characters are provided (null), the formatter uses mb_trim's default which includes all Unicode whitespace characters:

ASCII whitespace:

• (U+0020): Ordinary space
• \t (U+0009): Tab
• \n (U+000A): New line (line feed)
• \r (U+000D): Carriage return
• \0 (U+0000): NUL-byte
• \v (U+000B): Vertical tab
• \f (U+000C): Form feed

Unicode whitespace:

• U+00A0: No-break space
• U+1680: Ogham space mark
• U+2000–U+200A: Various width spaces (en quad, em quad, en space, em space, etc.)
• U+2028: Line separator
• U+2029: Paragraph separator
• U+202F: Narrow no-break space
• U+205F: Medium mathematical space
• U+3000: Ideographic space (CJK full-width space)
• U+0085: Next line (NEL)
• U+180E: Mongolian vowel separator

See mb_trim documentation for the complete list.