I want to always keep three element in array. So, I want if new element is added in array then oldest element will remove from array and Re-index array. Which is the best and fast way to make it?
This is my first array
$foo = array(
'when', // [0]
'whom', // [1]
'what' // [2]
);
If new element "how" added, I want to modify like below.
$foo = array(
'how', // [0]
'whom', // [1]
'what' // [2]
);
PHP has many built in array functions including array_unshift which allows you to add an element to the beginning and array_pop which allows you to remove an element from the end:
array_unshift($foo, 'how'); // Add to the beginning
array_pop($foo); // Remove from the end
Example: https://eval.in/859692
PHP scripts are no persistent, so I would suggest using time() as a key for each value. Then you know which one was put in first, and just write a function to overwrite the oldest.
<?php
$queue = [];
$queue_length = 3;
$add_item = function($item) use (&$queue, $queue_length) {
array_unshift($queue, $item) &&
count($queue) == $queue_length + 1 &&
array_pop($queue);
var_dump($queue);
};
$add_item('first');
$add_item('second');
$add_item('third');
$add_item('fourth');
$add_item('fifth');
Output:
array(1) {
[0]=>
string(5) "first"
}
array(2) {
[0]=>
string(6) "second"
[1]=>
string(5) "first"
}
array(3) {
[0]=>
string(5) "third"
[1]=>
string(6) "second"
[2]=>
string(5) "first"
}
array(3) {
[0]=>
string(6) "fourth"
[1]=>
string(5) "third"
[2]=>
string(6) "second"
}
array(3) {
[0]=>
string(5) "fifth"
[1]=>
string(6) "fourth"
[2]=>
string(5) "third"
}
The Fastest method You can Increase the More limit..
$array = ['One' => 1, 'Two' => 2, 'Three' => 3, 'Four' => 4, 'Five' => 5];
//selecting First 3 Arrays
foreach (new LimitIterator(new ArrayIterator($array), 0, 3) as $key => $val)
{
echo "$key => $val\n";
}
Give a Test
