Collator
PHP Manual

Collator::compare

collator_compare

Compare two Unicode strings

Description

Object-oriented style

public intfalse Collator::compare(string $string1, string $string2)

Procedural style

intfalse collator_compare(Collator $object, string $string1, string $string2)

Compare two Unicode strings according to collation rules.

Parameters

object

Collator object.

string1

The first string to compare.

string2

The second string to compare.

Return Values

Return comparison result:

  • 1 if string1 is greater than string2 ;

  • 0 if string1 is equal to string2;

  • -1 if string1 is less than string2 .

Returns false on failure.

Warning

This function may return Boolean false, but may also return a non-Boolean value which evaluates to false. Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

Examples

Example #1 collator_compare example

<?php
$s1 = 'Hello';
$s2 = 'hello';

$coll = collator_create( 'en_US' );
$res  = collator_compare( $coll, $s1, $s2 );

if ($res === false) {
    echo collator_get_error_message( $coll );
} else if( $res > 0 ) {
    echo "s1 is greater than s2\n";
} else if( $res < 0 ) {
    echo "s1 is less than s2\n";
} else {
    echo "s1 is equal to s2\n";
}
?>

The above example will output:


s1 is greater than s2

Example #2 Comparing strings without diacritics or case-sensitivity

<?php
$c = new Collator( 'en' );
$c->setStrength( Collator::PRIMARY );

if ( $c->compare( 'Séan', 'Sean' ) == 0 )
{
    echo "The same\n";
}

The above example will output:


The same

This example instructs the collator to compare with only taking the base characters into account. The documentation for Collator->setStrength explains the different strengths.

See Also

  • collator_sort