moodle/lib/adodb/adodb-pager.inc.php

<?php
/*
	V2.12 12 June 2002 (c) 2000-2002 John Lim (jlim@natsoft.com.my). All rights reserved.
	  Released under both BSD license and Lesser GPL library license. 
	  Whenever there is any discrepancy between the two licenses, 
	  the BSD license will take precedence. 
	  Set tabs to 4 for best viewing.

  	This class provides recordset pagination with 
	First/Prev/Next/Last links. 
	
	Feel free to modify this class for your own use as
	it is very basic. To learn how to use it, see the 
	example in adodb/tests/testpaging.php.
	
	Please note, this class is entirely unsupported, 
	and no free support requests except for bug reports
	will be entertained by the author.
	
	My company also sells a commercial pagination 
	object at http://phplens.com/ with much more 
	functionality, including search, create, edit,
	delete records. 
*/
class ADODB_Pager {
	var $id; 	/*  unique id for pager (defaults to 'adodb') */
	var $db; 	/*  ADODB connection object */
	var $sql; 	/*  sql used */
	var $rs;	/*  recordset generated */
	var $curr_page;	/*  current page number before Render() called, calculated in constructor */
	var $rows;		/*  number of rows per page */
	
	var $gridAttributes = 'width=100% border=1 bgcolor=white';
	
	/*  Localize text strings here */
	var $first = '<code>|&lt;</code>';
	var $prev = '<code>&lt;&lt;</code>';
	var $next = '<code>>></code>';
	var $last = '<code>>|</code>';
	var $page = 'Page';
	var $cache = 0;  #secs to cache with CachePageExecute()
	
	/* ---------------------------------------------- */
	/*  constructor */
	/*  */
	/*  $db	adodb connection object */
	/*  $sql	sql statement */
	/*  $id	optional id to identify which pager,  */
	/* 		if you have multiple on 1 page.  */
	/* 		$id should be only be [a-z0-9]* */
	/*  */
	function ADODB_Pager(&$db,$sql,$id = 'adodb')
	{
	global $HTTP_SERVER_VARS,$PHP_SELF,$HTTP_SESSION_VARS,$HTTP_GET_VARS;
	
		$curr_page = $id.'_curr_page';
		if (empty($PHP_SELF)) $PHP_SELF = $HTTP_SERVER_VARS['PHP_SELF'];
		
		$this->sql = $sql;
		$this->id = $id;
		$this->db = $db;
		
		$next_page = $id.'_next_page';	
		
		if (isset($HTTP_GET_VARS[$next_page])) {
			$HTTP_SESSION_VARS[$curr_page] = $HTTP_GET_VARS[$next_page];
		}
		if (empty($HTTP_SESSION_VARS[$curr_page])) $HTTP_SESSION_VARS[$curr_page] = 1; ## at first page
		
		$this->curr_page = $HTTP_SESSION_VARS[$curr_page];
		
	}
	
	/* --------------------------- */
	/*  Display link to first page */
	function Render_First($anchor=true)
	{
	global $PHP_SELF;
		if ($anchor) {
	?>
		<a href="<?php echo $PHP_SELF,'?',$this->id;?>_next_page=1"><?php echo $this->first;?></a> &nbsp; 
	<?php
		} else {
			print "$this->first &nbsp; ";
		}
	}
	
	/* -------------------------- */
	/*  Display link to next page */
	function render_next($anchor=true)
	{
	global $PHP_SELF;
	
		if ($anchor) {
		?>
		<a href="<?php echo $PHP_SELF,'?',$this->id,'_next_page=',$this->rs->AbsolutePage() + 1 ?>"><?php echo $this->next;?></a> &nbsp; 
		<?php
		} else {
			print "$this->next &nbsp; ";
		}
	}
	
	/* ------------------ */
	/*  Link to last page */
	/*   */
	/*  for better performance with large recordsets, you can set */
	/*  $this->db->pageExecuteCountRows = false, which disables */
	/*  last page counting. */
	function render_last($anchor=true)
	{
	global $PHP_SELF;
	
		if (!$this->db->pageExecuteCountRows) return;
		
		if ($anchor) {
		?>
			<a href="<?php echo $PHP_SELF,'?',$this->id,'_next_page=',$this->rs->LastPageNo() ?>"><?php echo $this->last;?></a> &nbsp; 
		<?php
		} else {
			print "$this->last &nbsp; ";
		}
	}
	
	/* ---------------------- */
	/*  Link to previous page */
	function render_prev($anchor=true)
	{
	global $PHP_SELF;
		if ($anchor) {
	?>
		<a href="<?php echo $PHP_SELF,'?',$this->id,'_next_page=',$this->rs->AbsolutePage() - 1 ?>"><?php echo $this->prev;?></a> &nbsp; 
	<?php 
		} else {
			print "$this->prev &nbsp; ";
		}
	}
	
	/* -------------------------------------------------------- */
	/*  Simply rendering of grid. You should override this for */
	/*  better control over the format of the grid */
	/*  */
	/*  We use output buffering to keep code clean and readable. */
	function RenderGrid()
	{
	global $gSQLBlockRows; /*  used by rs2html to indicate how many rows to display */
		include_once(ADODB_DIR.'/tohtml.inc.php');
		ob_start();
		$gSQLBlockRows = $this->rows;
		rs2html($this->rs,$this->gridAttributes);
		$s = ob_get_contents();
		ob_end_clean();
		return $s;
	}
	
	/* ------------------------------------------------------- */
	/*  Navigation bar */
	/*  */
	/*  we use output buffering to keep the code easy to read. */
	function RenderNav()
	{
		ob_start();
		if (!$this->rs->AtFirstPage()) {
			$this->Render_First();
			$this->Render_Prev();
		} else {
			$this->Render_First(false);
			$this->Render_Prev(false);
		}
		if (!$this->rs->AtLastPage()) {
			$this->Render_Next();
			$this->Render_Last();
		} else {
			$this->Render_Next(false);
			$this->Render_Last(false);
		}
		$s = ob_get_contents();
		ob_end_clean();
		return $s;
	}
	
	/* ------------------- */
	/*  This is the footer */
	function RenderPageCount()
	{
		if (!$this->db->pageExecuteCountRows) return '';
		return "<font size=-1>$this->page ".$this->curr_page."/".$this->rs->LastPageNo()."</font>";
	}
	
	/* ----------------------------------- */
	/*  Call this class to draw everything. */
	function Render($rows=10)
	{
	global $ADODB_COUNTRECS;
	
		$this->rows = $rows;
		
		$savec = $ADODB_COUNTRECS;
		if ($this->db->pageExecuteCountRows) $ADODB_COUNTRECS = true;
		if ($this->cache)
			$rs = &$this->db->CachePageExecute($this->cache,$this->sql,$rows,$this->curr_page);
		else
			$rs = &$this->db->PageExecute($this->sql,$rows,$this->curr_page);
		$ADODB_COUNTRECS = $savec;
		
		$this->rs = &$rs;
		if (!$rs) {
			print "<h3>Query failed: $this->sql</h3>";
			return;
		}
		
		if (!$rs->EOF && (!$rs->AtFirstPage() || !$rs->AtLastPage())) 
			$header = $this->RenderNav();
		else
			$header = "&nbsp;";
		
		$grid = $this->RenderGrid();
		$footer = $this->RenderPageCount();
		$rs->Close();
		$this->rs = false;
		
		$this->RenderLayout($header,$grid,$footer);
	}
	
	/* ------------------------------------------------------ */
	/*  override this to control overall layout and formating */
	function RenderLayout($header,$grid,$footer)
	{
		echo "<table border=1 bgcolor=beige><tr><td>",
				$header,
			"</td></tr><tr><td>",
				$grid,
			"</td></tr><tr><td>",
				$footer,
			"</td></tr></table>";
	}
}


?>