substr_compare

(PHP 5, PHP 7, PHP 8)

substr_compareBinary safe comparison of two strings from an offset, up to length characters

Опис

substr_compare(
    string $haystack,
    string $needle,
    int $offset,
    ?int $length = null,
    bool $case_insensitive = false
): int

substr_compare() compares haystack from position offset with needle up to length characters.

Параметри

haystack

The main string being compared.

needle

The secondary string being compared.

offset

The start position for the comparison. If negative, it starts counting from the end of the string.

length

The length of the comparison. The default value is the largest of the length of the needle compared to the length of haystack minus the offset.

case_insensitive

If case_insensitive is true, comparison is case insensitive.

Значення, що повертаються

Returns a value less than 0 if string1 is less than string2; a value greater than 0 if string1 is greater than string2, and 0 if they are equal. No particular meaning can be reliably inferred from the value aside from its sign.

If offset is equal to (prior to PHP 7.2.18, 7.3.5) or greater than the length of haystack, or the length is set and is less than 0, substr_compare() prints a warning and returns false.

Журнал змін

Версія Опис
8.2.0 Тепер ця функція повертає -1 або 1, а не від'ємне або додатнє число, як раніше.
8.0.0 length is nullable now.
7.2.18, 7.3.5 offset may now be equal to the length of haystack.

Приклади

Приклад #1 A substr_compare() example

<?php
echo substr_compare("abcde", "bc", 1, 2); // 0
echo substr_compare("abcde", "de", -2, 2); // 0
echo substr_compare("abcde", "bcg", 1, 2); // 0
echo substr_compare("abcde", "BC", 1, 2, true); // 0
echo substr_compare("abcde", "bc", 1, 3); // 1
echo substr_compare("abcde", "cd", 1, 2); // -1
echo substr_compare("abcde", "abc", 5, 1); // warning
?>

Прогляньте також

  • strncmp() - Binary safe string comparison of the first n characters