Home >Backend Development >PHP Tutorial >PHP recursive function Introduction to Array related functions in PHP
1. Use the function array_keys() to get all the keys in the array, parameter: array
$arr=array(); $arr['one']="one"; $arr['two']="two"; $arr['three']="three"; $newArr=array_keys($arr); print_r($newArr); //Array ( [0] => one [1] => two [2] => three )
2. Use the function array_values() to get all the values in the array, parameter: array
$arr=array(); $arr[20]="one"; $arr[30]="two"; $arr[40]="three"; $newArr=array_values($arr); print_r($newArr); //Array ( [0] => one [1] => two [2] => three )
3. Use the function array_map (), so that each element calls a custom function, parameters: String type function name, array
$arr=array(); $arr[0]="one"; $arr[1]="two"; $arr[2]="three"; function test($v){ return $v." Hello"; } $newArr=array_map("test",$arr); print_r($newArr); //Array ( [0] => one Hello [1] => two Hello [2] => three Hello )
4. Use the function array_merge() to merge two arrays into one, parameters: array, array
associative array When merging, those with the same key will be overwritten by the subsequent array. When the index arrays are merged, they will be connected together to form a new array.
$arr=array(); $arr[0]="one"; $arr[1]="two"; $arr[2]="three"; $arr1=array(); $arr[3]="taoshihan1"; $arr[4]="taoshihan2"; $arr[5]="taoshihan3"; $newArr=array_merge($arr,$arr1); print_r($newArr); //Array ( [0] => one [1] => two [2] => three [3] => taoshihan1 [4] => taoshihan2 [5] => taoshihan3 ) $arr=array("one","two","three"); $arr1=array("4","5","6"); $newArr=array_merge($arr,$arr1); print_r($newArr); //Array ( [0] => one [1] => two [2] => three [3] => 4 [4] => 5 [5] => 6 )5. Use the function ksort() to sort according to the key name. Note that no new ones are returned. Arrays are still the original arrays
$arr=array("2"=>"taoshihan2","1"=>"taoshihan1","3"=>"taoshihan3"); ksort($arr); print_r($arr); //Array ( [1] => taoshihan1 [2] => taoshihan2 [3] => taoshihan3 ) 使用函数array_search(),搜索某个键值,返回对应的键 $arr=array("2"=>"taoshihan2","1"=>"taoshihan1","3"=>"taoshihan3"); echo array_search("taoshihan1",$arr); // 1The above introduces the php recursive function Array related functions in PHP, including the content of php recursive functions. I hope it will be helpful to friends who are interested in PHP. Related articles:
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