Is it possible to set PHP's internal array pointer without first iterating through the array. Take the following dummy code as example:
$array = range(1, 100); // Represents the array key $pointer = 66; set_array_pointer($pointer, $array); $nextValue = next($array); // Should return 68 4 Answers
Answers 1
The solution LibertyPaul provided using ArrayIterator::seek seems to be the only way to make php set a pointer to a position within an array without initializing looping in userland. php will internally loop through the array to set the pointer, though, as you can read from the php source of ArrayIterator::seek():
/* {{{ proto void ArrayIterator::seek(int $position) Seek to position. */ SPL_METHOD(Array, seek) { zend_long opos, position; zval *object = getThis(); spl_array_object *intern = Z_SPLARRAY_P(object); HashTable *aht = spl_array_get_hash_table(intern); int result; if (zend_parse_parameters(ZEND_NUM_ARGS(), "l", &position) == FAILURE) { return; } if (!aht) { php_error_docref(NULL, E_NOTICE, "Array was modified outside object and is no longer an array"); return; } opos = position; if (position >= 0) { /* negative values are not supported */ spl_array_rewind(intern); result = SUCCESS; while (position-- > 0 && (result = spl_array_next(intern)) == SUCCESS); if (result == SUCCESS && zend_hash_has_more_elements_ex(aht, spl_array_get_pos_ptr(aht, intern)) == SUCCESS) { return; /* ok */ } } zend_throw_exception_ex(spl_ce_OutOfBoundsException, 0, "Seek position %pd is out of range", opos); } /* }}} */ So it looks like there is no way to set an array-pointer to a certain position without looping through the array
Answers 2
You can do this with ArrayObject and ArrayIterator:
$array = range(1, 100); $pointer = 66; $arrayobject = new ArrayObject($array); $iterator = $arrayobject->getIterator(); $iterator->seek($pointer); //set position $iterator->next(); // move iterator $nextValue = $iterator->current(); Answers 3
you can define your own function using next() and reset() to use pointer and use like below code
<?php function findnext (&$array,$key) { reset ($array); while (key($array) !== $key) { if (next($array) === false) throw new Exception('can not find key'); } } $array = range(1, 100); $pointer = 66; findnext($array,$pointer); echo next($array); //this will give 68 ?> Answers 4
You don't need to set actual pointer for array. php already has support for internal array pointers see next() method:
$transport = array('foot', 'bike', 'car', 'plane'); $mode = current($transport); // $mode = 'foot'; $mode = next($transport); // $mode = 'bike'; $mode = next($transport); // $mode = 'car'; $mode = prev($transport); // $mode = 'bike'; $mode = end($transport); // $mode = 'plane'; 
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