One paging navigation class

? Php + versions + | PHPVersion4 | + ---------------------------------------------------------------------- + | Copyright (c) 1997-2002ThePHPGroup | + ------------------------ // + ------------------------------------------------------------------------ +
// | PHP Version 4 |
// + ------------------------------------------------------------------------ +
// | Copyright (c) 1997-2002 The PHP Group |
// + ------------------------------------------------------------------------ +
// | This source file is subject to version 2.02 of the PHP license, |
// | That is bundled with this package in the file LICENSE, and is |
// | Available at through the world-wide-web at |
// | Http://www.php.net/license/2_02.txt. |
// | If you did not receive a copy of the PHP license and are unable to |
// | Obtain it through the world-wide-web, please send a note to |
// License@php.net so we can mail you a copy immediately. |
// + ------------------------------------------------------------------------ +
// | Authors: Richard Heyes |
// + ------------------------------------------------------------------------ +

/**
* Pager class
*
* Handles paging a set of data. For usage see the example. php provided.
*
*/

Class Pager {

/**
* Current page
* @ Var integer
*/
Var $ _ currentPage;

/**
* Items per page
* @ Var integer
*/
Var $ _ perPage;

/**
* Total number of pages
* @ Var integer
*/
Var $ _ totalPages;

/**
* Item data. Numerically indexed array...
* @ Var array
*/
Var $ _ itemData;

/**
* Total number of items in the data
* @ Var integer
*/
Var $ _ totalItems;

/**
* Page data generated by this class
* @ Var array
*/
Var $ _ pageData;

/**
* Constructor
*
* Sets up the object and calculates the total number of items.
*
* @ Param $ params An associative array of parameters This can contain:
* CurrentPage Current Page number (optional)
* PerPage Items per page (optional)
* ItemData Data to page
*/
Function pager ($ params = array ())
{
Global $ HTTP_GET_VARS;

$ This-> _ currentPage = max (int) @ $ HTTP_GET_VARS ['pageid'], 1 );
$ This-> _ perPage = 8;
$ This-> _ itemData = array ();

Foreach ($ params as $ name => $ value ){
$ This-> {'_'. $ name} = $ value;
}

$ This-> _ totalItems = count ($ this-> _ itemData );
}

/**
* Returns an array of current pages data
*
* @ Param $ pageID Desired page ID (optional)
* @ Return array Page data
*/
Function getPageData ($ pageID = null)
{
If (isset ($ pageID )){
If (! Empty ($ this-> _ pageData [$ pageID]) {
Return $ this-> _ pageData [$ pageID];
} Else {
Return FALSE;
}
}

If (! Isset ($ this-> _ pageData )){
$ This-> _ generatePageData ();
}

Return $ this-> getPageData ($ this-> _ currentPage );
}

/**
* Returns pageID for given offset
*
* @ Param $ index Offset to get pageID
* @ Return int PageID for given offset
*/
Function getPageIdByOffset ($ index)
{
If (! Isset ($ this-> _ pageData )){
$ This-> _ generatePageData ();
}

If ($ index % $ this-> _ perPage)> 0 ){
$ PageID = ceil (float) $ index/(float) $ this-> _ perPage );
} Else {
$ PageID = $ index/$ this-> _ perPage;
}

Return $ pageID;
}

/**
* Returns offsets for given pageID. Eg, if you
* Pass it pageID one and your perPage limit is 10
* It will return you 1 and 10. PageID of 2 wowould
* Give you 11 and 20.
*
* @ Params pageID PageID to get offsets
* @ Return array First and last offsets
*/
Function getOffsetByPageId ($ pageid = null)
{
$ Pageid = isset ($ pageid )? $ Pageid: $ this-> _ currentPage;
If (! Isset ($ this-> _ pageData )){
$ This-> _ generatePageData ();
}

If (isset ($ this-> _ pageData [$ pageid]) {
Return array ($ this-> _ perPage * ($ pageid-1) + 1, min ($ this-> _ totalItems, $ this-> _ perPage * $ pageid ));
} Else {
Return array (0, 0 );
}
}

/**
* Returns back/next and page links
*
* @ Param $ back_html HTML to put inside the back link
* @ Param $ next_html HTML to put inside the next link
* @ Return array Back/pages/next links
*/
Function getLinks ($ back_html = '<back', $ next_html = 'next> ')
{
$ Url = $ this-> _ getLinksUrl ();
$ Back = $ this-> _ getBackLink ($ url, $ back_html );
$ Pages = $ this-> _ getPageLinks ($ url );
$ Next = $ this-> _ getNextLink ($ url, $ next_html );

Return array ($ back, $ pages, $ next, 'back' => $ back, 'Pages '=> $ pages, 'next' => $ next );
}

/**
* Returns number of pages
*
* @ Return int Number of pages
*/
Function numPages ()
{
Return $ this-> _ totalPages;
}

/**
* Returns whether current page is first page
*
* @ Return bool First page or not
*/
Function isFirstPage ()
{
Return ($ this-> _ currentPage = 1 );
}

/**
* Returns whether current page is last page
*
* @ Return bool Last page or not
*/
Function isLastPage ()
{
Return ($ this-> _ currentPage = $ this-> _ totalPages );
}

/**
* Returns whether last page is complete
*
* @ Return bool Last age complete or not
*/
Function isLastPageComplete ()
{
Return! ($ This-> _ totalItems % $ this-> _ perPage );
}

/**
* Calculates all page data
*/
Function _ generatePageData ()
{
$ This-> _ totalItems = count ($ this-> _ itemData );
$ This-> _ totalPages = ceil (float) $ this-> _ totalItems/(float) $ this-> _ perPage );
$ I = 1;
If (! Empty ($ this-> _ itemData )){
Foreach ($ this-> _ itemData as $ value ){
$ This-> _ pageData [$ I] [] = $ value;
If (count ($ this-> _ pageData [$ I]) >=$ this-> _ perPage ){
$ I ++;
}
}
} Else {
$ This-> _ pageData = array ();
}
}

/**
* Returns the correct link for the back/pages/next links
*
* @ Return string Url
*/
Function _ getLinksUrl ()
{
Global $ HTTP_SERVER_VARS;

// Sort out query string to prevent messy urls
$ Querystring = array ();
If (! Empty ($ HTTP_SERVER_VARS ['query _ string']) {
$ Qs = explode ('&', $ HTTP_SERVER_VARS ['query _ string']);
For ($ I = 0, $ cnt = count ($ qs); $ I <$ cnt; $ I ++ ){
List ($ name, $ value) = explode ('=', $ qs [$ I]);
If ($ name! = 'Pageid '){
$ Qs [$ name] = $ value;
}
Unset ($ qs [$ I]);
}
}
If (is_array ($ qs )){
Foreach ($ qs as $ name => $ value ){
$ Querystring [] = $ name. '='. $ value;
}
}
Return $ HTTP_SERVER_VARS ['script _ name']. '? '. Implode (' & ', $ querystring ).(! Empty ($ querystring )? '&': '). 'Pageid = ';
}

/**
* Returns back link
*
* @ Param $ url URL to use in the link
* @ Param $ link HTML to use as the link
* @ Return string The link
*/
Function _ getBackLink ($ url, $ link = '<back ')
{
// Back link
If ($ this-> _ currentPage> 1 ){
$ Back = '_ currentPage-1).' "> '. $ link .'';
} Else {
$ Back = ';
}

Return $ back;
}

/**
* Returns pages link
*
* @ Param $ url URL to use in the link
* @ Return string Links
*/
Function _ getPageLinks ($ url)
{
// Create the range
$ Params ['itemdata'] = range (1, max (1, $ this-> _ totalPages ));
$ Pager = & new Pager ($ params );
$ Links = $ pager-> getPageData ($ pager-> getPageIdByOffset ($ this-> _ currentPage ));

For ($ I = 0; $ I If ($ links [$ I]! = $ This-> _ currentPage ){
$ Links [$ I] = '_ getLinksUrl (). $ links [$ I].' "> '. $ links [$ I].'';
}
}

Return implode ('', $ links );
}

/**
* Returns next link
*
* @ Param $ url URL to use in the link
* @ Param $ link HTML to use as the link
* @ Return string The link
*/
Function _ getNextLink ($ url, $ link = 'next> ')
{
If ($ this-> _ currentPage <$ this-> _ totalPages ){
$ Next = '_ currentPage + 1).' "> '. $ link .'';
} Else {
$ Next = ';
}

Return $ next;
}
}

?>