dictionary.php

См. документацию.

<?php
 
namespace Bitrix\Main\Type;
 
class Dictionary implements \ArrayAccess, \Iterator, \Countable, \JsonSerializable
{
    protected $values = [];

    public function __construct(array $values = null)
    {
        if($values !== null)
        {
            $this->values = $values;
        }
    }

    public function get($name)
    {
        // this condition a bit faster
        // it is possible to omit array_key_exists here, but for uniformity...
        if (isset($this->values[$name]) || \array_key_exists($name, $this->values))
        {
            return $this->values[$name];
        }
 
        return null;
    }
 
    public function set($name, $value = null)
    {
        if (\is_array($name))
        {
            $this->values = $name;
        }
        else
        {
            $this[$name] = $value;
        }
    }

    public function getValues()
    {
        return $this->values;
    }

    public function setValues($values)
    {
        $this->values = $values;
    }
 
    public function clear()
    {
        $this->values = [];
    }

    #[\ReturnTypeWillChange]
    public function current()
    {
        return current($this->values);
    }

    public function next(): void
    {
        next($this->values);
    }

    #[\ReturnTypeWillChange]
    public function key()
    {
        return key($this->values);
    }

    public function valid(): bool
    {
        return (key($this->values) !== null);
    }

    public function rewind(): void
    {
        reset($this->values);
    }

    public function offsetExists($offset): bool
    {
        return isset($this->values[$offset]) || \array_key_exists($offset, $this->values);
    }

    #[\ReturnTypeWillChange]
    public function offsetGet($offset)
    {
        if (isset($this->values[$offset]) || \array_key_exists($offset, $this->values))
        {
            return $this->values[$offset];
        }
 
        return null;
    }

    #[\ReturnTypeWillChange]
    public function offsetSet($offset, $value)
    {
        if($offset === null)
        {
            $this->values[] = $value;
        }
        else
        {
            $this->values[$offset] = $value;
        }
    }

    public function offsetUnset($offset): void
    {
        unset($this->values[$offset]);
    }

    public function count(): int
    {
        return \count($this->values);
    }

    public function toArray()
    {
        return $this->values;
    }

    public function isEmpty()
    {
        return empty($this->values);
    }

    #[\ReturnTypeWillChange]
    public function jsonSerialize()
    {
        return $this->values;
    }
 
    public function __unserialize(array $data): void
    {
        if (isset($data['values']) && is_array($data['values']))
        {
            $this->values = $data['values'];
        }
    }
}