MaskFormatter

The MaskFormatter enables masking sensitive text data using intuitive range-based patterns.

Usage

Basic Usage

use Respect\StringFormatter\MaskFormatter;

$formatter = new MaskFormatter('1-3,8-12');

echo $formatter->format('1234123412341234');
// Outputs: ***4123*****1234

Custom Replacement Character

use Respect\StringFormatter\MaskFormatter;

$formatter = new MaskFormatter('1-3,8-12', '#');

echo $formatter->format('1234123412341234');
// Outputs: ###4123#####1234

API

MaskFormatter::__construct

• __construct(string $range, string $replacement = '*')

Creates a new formatter instance with the specified range and replacement character.

Parameters:

• $range: Comma-separated range specifications
• $replacement: The character to use for masking (default *)

Throws: InvalidArgumentException when invalid ranges are provided

format

• format(string $input): string

Formats the input string according to the range specified in the constructor.

Parameters:

• $input: The string to format

Returns: The formatted string

Range Syntax

Pattern	Description	Example
N	Single position (1-based)	3
N-	From position N to end	1-
N-M	Range from position N to M	1-3
-N	Last N characters	-3
C-M	From character C to character M	1-@
\N	Escaped numeral character	\5
\C	Escaped special character	\-, \,, or \\

Multiple ranges can be specified using commas: 1-B,6-8,10

Numeric Positions (1-based)

Use numeric positions to mask specific characters (1-based indexing).

Range	Input	Output
1-3	password123	***ord123
1-3	'12345'	***45
7-12	'1234567890'	123456******

Character Delimiters

Use character delimiters to mark ranges between characters in the string.

Range	Input	Output
1-@	username@domain.com	********@domain.com
A-\5	ABCDD1234567890EFGH	*********567890EFGH
A-\-	ABCD-1234567890EFGH	####-1234567890EFGH
B-\,	ABC,DEF,GHI	**C,DEF,GHI

Multiple Ranges

Combine multiple ranges using commas to mask non-contiguous sections.

Range	Input	Output
1-3,8-12	1234123412341234	***4123*****1234
1,3,5	'12345'	*2*4*
1-3,6-8,10	abcdefghij	***de***j
1,3,5	12345	*2*4*
1-3,8-12	'123456789012'	***45678******
A-D,5-8	ABCD1234567890EFGH	####D####567890EFGH
1-c,2-5	abc123def456	#####3def456

Special Patterns

Mask to end: Use 1- to mask from the beginning to the end
Mask last N: Use -N to mask the last N characters

Range	Input	Output
1-	12345678	********
-2	123456	1234**
-3	abcdefgh	abcde***

Escaping Special Characters

Escape special characters with backslash when they need to be used as literals.

Range	Input	Output
3-\5	1234567890	12**567890
1-\-	email-something@domain.com	*****-something@domain.com
1-\\\\	path\to\file	****\to\file

To use -, \ and , as delimiters, you must always add backslashes before them.

Unicode Support

Full support for UTF-8 strings including accented characters.

Range	Input	Output
1-	oftalmoscópico	**************
2-6,9	áéíóúãõçüñ	á*****õç*ñ
-4	españolñç	españolñ*