Record the paging method of PHP array data

Our data may not be stored in databases, and is often organized using arrays. Therefore, it is a common programming requirement to retrieve array data and paging. The paging principle is very simple, that is, to obtain data in a certain range by the number of pages. PHP provides us with a very convenient function: array_slice (). The array_slice () function extracts a value from the Array Based on the Conditions and returns it.

The following two paging examples are simple.

Public function books ($ pagenum = 1) {include_once ("page. php "); include (" arr_books.php "); foreach ($ data ['books '] as $ key => $ value) {$ name [$ key] = $ value ['name']; $ rank [$ key] = $ value ['rank '];} array_multisort ($ rank, SORT_NUMERIC, SORT_DESC, $ data ['books ']); // Reverse Order // array_multisort ($ rank, SORT_NUMERIC, SORT_ASC, $ data ['books']); // order $ perpage = 10; $ count = count ($ data ['books ']); $ pages = new PageClass ($ count, $ perpage, $ pagenum, base_url (). 'veda/books/{page}/'); $ start = ($ pagenum-1) * $ perpage; $ data ['bks '] = array_slice ($ data ['books'], $ start, $ perpage ); $ data ['nav'] = $ pages-> myde_write ($ pagenum); $ this-> load-> view ('header', $ data ); $ this-> load-> view ('books ', $ data); $ this-> load-> view ('footer', $ data );}

Next:

$perpage = 2;$page = intval(getgpc('page')) ? intval($_G['gp_page']) : 1;$start = ($page - 1) * $perpage;$count = count($group_list);$list = array_slice($group_list, $start, $perpage);$multipage = multi($count, $perpage, $page, "home.php?mod=space&do=group&type=".getgpc('type'));

Array_slice () function

The array_slice () function extracts a value from the Array Based on the Conditions and returns it. If the array has a string key, the returned array retains the key name.

Syntax: array_slice (array, offset, length, preserve)

Parameters	Description
Array	Required. Specifies the input array.
Offset	Required. Value. Specifies the start position of the retrieved element. If it is a positive number, it is taken from the beginning to the end. If it is a negative value, it is taken from the back to the absolute value of the offset.
Length	Optional. Value. Specifies the length of the returned array. If it is a negative number, select the element of the absolute value from the back to the front. If this value is not set, all elements are returned.
Preserve	Optional. Possible values: True-reserved key False-default-Reset key

Example 1:

<?php$a=array(0=>"Dog",1=>"Cat",2=>"Horse",3=>"Bird");print_r(array_slice($a,1,2));// Array ( [0] => Cat [1] => Horse )?>

Example 2 (with a negative offset parameter ):

<?php$a=array(0=>"Dog",1=>"Cat",2=>"Horse",3=>"Bird");print_r(array_slice($a,-2,1));// Array ( [0] => Horse )?>

Example 3 (set the preserve parameter to true ):

<?php$a=array(0=>"Dog",1=>"Cat",2=>"Horse",3=>"Bird");print_r(array_slice($a,1,2,true));// Array ( [1] => Cat [2] => Horse )?>

Example 4 (with a string key ):

<?php$a=array("a"=>"Dog","b"=>"Cat","c"=>"Horse","d"=>"Bird");print_r(array_slice($a,1,2));// Array ( [b] => Cat [c] => Horse )?>