contains

Note

This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information.

Returns whether the "haystack" string contains the "needle" string

namespace HH\Lib\Str;

function contains(
  string $haystack,
  string $needle,
  int $offset = 0,
): bool;

An optional offset determines where in the haystack the search begins. If the offset is negative, the search will begin that many characters from the end of the string. If the offset is out-of-bounds, a ViolationException will be thrown.

• To get the position of the needle, see Str\search().
• To search for the needle case-insensitively, see Str\contains_ci().

Guide

• String

Parameters

• string $haystack
• string $needle
• int $offset = 0

Returns

• bool

Examples

$result = Str\contains("example_string", "example");
echo($result);
//result: true 

$result = Str\contains("example_string", "EXAMPLE"); // different case
echo($result);
//result: false

$result = Str\contains("example_string", "example", 2); // with offset
echo($result);
//result: false 

$result = Str\contains("example_string", "uncontained");
echo($result);
//result: false