Basic operations on PHP arrays and classic operation instances for Traversing arrays, basic operations on Arrays

Basic operations on PHP arrays and classic operation instances for Traversing arrays, basic operations on Arrays

The instance is as follows:

<? Php Index array // array first definition $ arr = array (, 3); var_dump ($ arr); // array second definition $ arr = [, 3]; var_dump ($ arr); // The third definition of the array $ arr [0] = 7; $ arr [1] = "hello"; var_dump ($ arr ); echo $ arr [2]; // value Association array $ arr = array ("name" => "Lee", "sex" => "female ", "age" => "20"); echo $ arr ["sex"]; traversal array // for Loop traversal applies to index arrays $ arr =, 8]; for ($ I = 0; $ I <count ($ arr); $ I ++) {echo $ arr [$ I]. '<br>' ;}; // foreach loop traversal applies to indexes and associated arrays $ arr = array ("name" => "Xiao Li ", "sex" => "female", "age" => "20"); foreach ($ arr as $ k => $ v) {// echo $ k. ':'. $ v. '<br>'; echo "{$ k }:{ $ v} <br>" ;}; $ arr = [, 8]; foreach ($ arr as $ k) {echo $ k. '<br>' ;}; $ arr = array ("name" => "Lee", "sex" => "female ", "age" => "20"); var_dump (each ($ arr); list ($ a, $ B) = array (name, Xiao Li ); echo "{$ a}, {$ B}"; list and each combine to traverse/* $ arr = array ("name" => "Xiao Li ", "sex" => "female", "age" => "20"); while (list ($ k, $ v) = each ($ arr )) {echo "{$ k }:{$ v} <br>" ;}*/pointer traversal/* $ arr = array ("name" => "Xiao Li ", "sex" => "female", "age" => "20"); echo current ($ arr); // obtain valueecho key ($ arr ); // obtain keynext ($ arr); echo current ($ arr); echo key ($ arr); prev ($ arr); echo current ($ arr ); echo key ($ arr); end ($ arr); echo current ($ arr); echo key ($ arr); reset ($ arr); echo key ($ arr ). ':'. current ($ arr ). '<br> ';*/

The basic operation of the above PHP array and the classic operation instance for traversing the array are all the content shared by the editor. I hope you can give us a reference and support for the help house.