php常用数组array函数实例总结【赋值,拆分,合并,计算,添加,删除,查询,判断,排序】

本文实例总结了php常用数组array函数。分享给大家供大家参考,具体如下:

array_combine

功能:用一个数组的值作为新数组的键名,另一个数组的值作为新数组的值

案例:

<?php
$a = array("one","two","three");
$b = array("一","二","三");
$c = array_combine($a,$b);
print_r($c);
/**结果
*Array ( [one] => 一 [two] => 二 [three] => 三 )
*/

array_chunk

功能:拆分数组成多个数组

<?php
$input_array = array("a"=>"apple","b"=>"blue","c","d","e");
echo "<pre>";
print_r(array_chunk($input_array, ));
print_r(array_chunk($input_array, ,True));
echo "</pre>";
/**结果
Array
(
[0] => Array
(
[0] => apple
[1] => blue
)
[1] => Array
(
[0] => c
[1] => d
)
[2] => Array
(
[0] => e
)
)
Array
(
[0] => Array
(
[a] => apple
[b] => blue
)
[1] => Array
(
[0] => c
[1] => d
)
[2] => Array
(
[2] => e
)
)
*/

array_count_values

功能:统计数组中值出现的次数

<?php
$input_array = array("a"=>"apple","b"=>"blue","c","d","e");
echo "<pre>";
print_r(array_count_values($input_array));
echo "</pre>";
/**结果
Array
(
[apple] => 1
[blue] => 1
[c] => 1
[d] => 1
[e] => 1
)
*/

array_diff

功能:第一个数组中去掉第二个数组中有的数据,返回剩下的内容作为结果

<?php
$array1 = array("a"=>"apple","b"=>"blue","c","d","e");
$array2 = array("apple","c","d","f");
$result = array_diff($array1, $array2);
$result2 = array_diff($array2, $array1);
echo "<pre>";
print_r($result);//数组1中去掉数组2中剩下的
print_r($result2);//数组2中去掉数组1中剩下的
echo "</pre>";
/**结果
Array
(
[b] => blue
[2] => e
)
Array
(
[3] => f
)
*/

array_map

功能:将回调函数执行到数组中

<?php
//定义回调函数
function cube($n){
return ($n*$n*$n);
}
$a = array(,,,,);
$b = array_map("cube",$a);
echo "<pre>";
print_r($b);
echo "</pre>";
/**结果
Array
(
[0] => 1
[1] => 8
[2] => 27
[3] => 64
[4] => 125
)
*/

array_merge

功能:合并一个或多个数组

说明:如果后面有键名相同的会覆盖掉前面的内容,键名为数字的会添加到后面

<?php
$array1 = array("color"=>"red",,);
$array2 = array("a","b","color"=>"green","shape"=>"trapezoid",);
$result1 = array_merge($array1,$array2);
$result2 = array_merge_recursive($array1,$array2);
echo "<pre>";
print_r($result1);
print_r($result2);
echo "</pre>";
/**结果
Array
(
[color] => green
[0] => 2
[1] => 4
[2] => a
[3] => b
[shape] => trapezoid
[4] => 4
)
Array
(
[color] => Array
(
[0] => red
[1] => green
)
[0] => 2
[1] => 4
[2] => a
[3] => b
[shape] => trapezoid
[4] => 4
)
*/

array_pop

功能:剔除数组最后一个元素,返回被剔除的元素内容

<?php
$stack = array("orange","banana","apple","");
$last = array_pop($stack);
echo "<pre>";
print_r($stack);
print_r($last);
echo "</pre>";
/**结果
Array
(
[0] => orange
[1] => banana
[2] => apple
)
1
*/

array_push

功能:将一个多个单元压入数组末尾,返回之后的数组个数

<?php
$stack = array("orange","banana");
$count = array_push($stack,"apple","red","blue");
echo "<pre>";
print_r($stack);
print_r($count);
echo "</pre>";
/**结果
Array
(
[0] => orange
[1] => banana
[2] => apple
[3] => red
[4] => blue
)
5
*/

array_rand

功能:获取随机的键名

<?php
$input = array("orange","banana","apple","red","blue");
$rand = array_rand($input,);;
print_r($rand);
$rand = array_rand($input,);
print_r($rand);
/**结果
Array
(
[0] => 1
[1] => 4
)
Array
(
[0] => 0
[1] => 1
[2] => 3
)
*/

array_search

功能:查询数组中的内容,返回键值,如果有多个匹配,返回第一个匹配的内容

<?php
$array = array("blue"=>"b","red"=>"r","green","r");
$key = array_search('b', $array);
echo $key;
echo "<br>";
$key = array_search('r', $array);
echo $key;
echo "<br>";
/**结果
blue
red
*/
array_shift

功能:移除开头的元素,与array_pop相反
<?php
$fruit = array("milk","orange","banana","apple");
$top = array_shift($fruit);
print_r($top);
echo "<br>";
print_r($fruit);
/**结果
milk
Array ( [0] => orange [1] => banana [2] => apple )
*/

array_unique

功能:去除数组重复的元素,保留第一个出现的,包括键名和值

<?php
$input = array("a"=>"green","red","b"=>"green","blue","c"=>"red");
$result = array_unique($input);
print_r($result);
echo "<br>";
print_r($input);
/**结果
Array ( [a] => green [0] => red [1] => blue )
Array ( [a] => green [0] => red [b] => green [1] => blue [c] => red )
*/

array_slice

功能:从数组中取出部分元素

<?php
$input = array("a","b","c","d","e");
$output = array_slice($input,);//第二个参数没有时,表示取到最后一个元素
print_r($output);
echo "<br>";
$output = array_slice($input,-,);//第二个参数是正数时,表示个数;倒数第一个是-1,倒数第二个是-2
print_r($output);
echo "<br>";
$output = array_slice($input,,);
print_r($output);
echo "<br>";
$output = array_slice($input,,-);//第二个参数是负数时,表示位置,取到哪一位,不包括本身
print_r($output);
echo "<br>";
$output = array_slice($input,,-,true);//第三个参数为true时,保留原有的键值
print_r($output);
echo "<br>";
/**结果
Array ( [0] => c [1] => d [2] => e )
Array ( [0] => d )
Array ( [0] => a [1] => b [2] => c )
Array ( [0] => c [1] => d )
Array ( [2] => c [3] => d )
*/

count

功能:返回数组元素个数,元素为数组的算一个

<?php
$input = array("a","b","c",array("d","e"));
$count = count($input);
echo $count;
echo "<br>";
$input = array("a","b","c","d","e");
$count = count($input);
echo $count;
/**结果
4
5
*/

in_array

功能:检验某值是否存在数组中,有返回True,没有返回False

<?php
$os_list = array("Mac","NT","Irix","Linux");
if(in_array("Irix",$os_list)){
echo "当前操作系统列表中存在Irix";
}else{
echo "当前操作系统列表中不存在Irix";
}
echo "<br>";
if(in_array("mac",$os_list)){
echo "当前操作系统列表中存在mac";
}else{
echo "当前操作系统列表中不存在mac";
}
echo "<br>";
/**结果
当前操作系统列表中存在Irix
当前操作系统列表中不存在mac
*/

list

功能:将数组中的信息赋值给多个变量

<?php
$info = array("red","blue","green");
list($flag,$sky,$grassland) = $info;
echo "$flag,$sky,$grassland";
echo "<br>";
list($flag,,$grassland) = $info;
echo "$flag,$grassland";
echo "<br>";
list(,,$grassland) = $info;
echo "$grassland";
echo "<br>";
/**结果
red,blue,green
red,green
green
*/

shuffle

功能:打乱数组

<?php
$numbers = range(,);//生成一个随机数组
print_r($numbers);
echo "<br/>";
shuffle($numbers);//打乱数组
print_r($numbers);
/**结果
Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 )
Array ( [0] => 4 [1] => 1 [2] => 5 [3] => 2 [4] => 3 )
*/

array_keys

功能:获取数组的键名,第二个参数可以指定获取某个元素

<?php
$array = array(=>,"color"=>"red");
print_r(array_keys($array));
echo "<br>";
$array = array("blue","red","green","blue","blue");
print_r(array_keys($array,"blue"));
echo "<br>";
$array = array("color"=>array("blue","red","green"),"size"=>array("small","medium","large"));
print_r(array_keys($array));
echo "<br>";
/**结果
Array ( [0] => 0 [1] => color )
Array ( [0] => 0 [1] => 3 [2] => 4 )
Array ( [0] => color [1] => size )
*/

array_reverse

功能:获取数组的反向

<?php
$input = array("php",3.0,array("green","red"));
$result = array_reverse($input); //打乱键名
$result_keyed = array_reverse($input,TRUE);//保留键名
print_r($result);
print_r($result_keyed);
/**结果
Array
(
[0] => Array
(
[0] => green
[1] => red
)
[1] => 3
[2] => php
)
Array
(
[2] => Array
(
[0] => green
[1] => red
)
[1] => 3
[0] => php
)
*/
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