PHP commonly used array manipulation functions

We have many elements that operate on arrays, let’s talk about some of them first in this section. In 6.3 we will summarize more common array functions.

The following functions are mainly used to move the array pointer and push in and pop out array elements.

##array_shiftPop array The first element inarray_unshiftPush the element at the beginning of the arrayarray_pushPush elements to the end of the arrayarray_popPop the last element at the end of the arraycurrentRead the value of the current position of the pointer#keyRead the key of the current position of the pointer nextMove the pointer downprevMove upresetPointer to the beginningendPointer to the end

array_shift

##mixed array_shift ( array &$array )

Function: Pop the first element in the array

<?php
$mingren = array("邓超", "黄晓明", "宁泽涛", "钟汉良");
$dc = array_shift($mingren);

echo $dc .'<br />';

print_r($mingren);
?>

Execution result:

Conclusion:

1. Pop out the first array element, changing the result of the original array

2. The pop-up value is assigned to $dc

array_unshift

int array_unshift (array &$array, mixed $value 1 [, mixed $... ] )

Function: Push one or more elements to the beginning of the index array, and return the total number.

<?php
$mingren = array("邓超", "黄晓明");
$dc = array_unshift($mingren , "宁泽涛", "钟汉良");

echo $dc .'<br />';

print_r($mingren);
?>

The execution results are as follows:

array_pop

mixed array_pop (array &$array)

Function: pop up an element at the end of the array

<?php
$mingren = array("邓超", "黄晓明", "宁泽涛", "钟汉良");
$dc = array_pop($mingren);

echo $dc .'<br />';

print_r($mingren);
?>

Execution result:

array_push

##int array_push ( array &$array , mixed $value1 [, mixed $... ] )

Function: Push one or more elements to the end of the index array, and return the total number.

<?php
$mingren = array("邓超", "黄晓明");
$dc = array_push($mingren , "宁泽涛", "钟汉良");

echo $dc .'<br />';

print_r($mingren);
?>

Execution result:

#current,key,prev,next,reset function demonstration

The functions of these functions have been explained very clearly. We demonstrate through code:

<?php
$t=array(
   '我们',
   'yy'=>'永远',
   'dbg'=>'需要不断奋进',
   'djn'=>'才能开创未来'
   );


//读取数组的值
echo current($t).'<br />';
//读取数组的键
echo key($t).'<br />';

//向后移动一下
next($t);

//再读值和键
echo current($t).'<br />';

echo key($t).'<br />';


//向后移动一下
next($t);
echo current($t).'<br />';

echo key($t).'<br />';


//向前移动一下
prev($t);
echo current($t).'<br />';
echo key($t).'<br />';


//移到末尾
end($t);
echo current($t).'<br />';
echo key($t).'<br />';

//移至开始处
reset($t);
echo current($t).'<br />';

echo key($t).'<br />';


//销毁数组
unset($t);
var_dump($t);
?>

Continuing Learning

Function	Function