PHP二维数组分页2种实现方法解析

<?php
$arr_click = array(
  array( 'clicks' =  3, 'clickDate' = '2010-10-11' ),
  array( 'clicks' =  2, 'clickDate' = '2010-10-11' ),
  array( 'clicks' =  3, 'clickDate' = '2010-10-09' ),
  array( 'clicks' =  1, 'clickDate' = '2010-10-08' ),
);
$page = 2;
$indexinpage=2;
$newarr = array_slice($arr_click, ($page-1)*$indexinpage, $indexinpage);
? 

<?php
$arr_click = array(
  array( 'clicks' =  3, 'clickDate' = '2010-10-11' ),
  array( 'clicks' =  2, 'clickDate' = '2010-10-11' ),
  array( 'clicks' =  3, 'clickDate' = '2010-10-09' ),
  array( 'clicks' =  1, 'clickDate' = '2010-10-08' ),
);
$size = 3;
$pnum = ceil(count($arr_click) / $size);
if(isset($_GET['page'])){
  $page = intval($_GET['page']);
  $page = $page   $pnum? $pnum: $page;
  $page = $page < $pnum? 1: $page;
}else{
  $page = 1;
}
for($i = 0; $i < $size; $i++){
  if(!isset($arr_click[($page - 1) * $size + $i]))break;
  echo '<pre ';
  print_r($arr_click[($page - 1) * $size + $i]);
  echo '<br ';
}
? 
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<a href="ad.php?page=<?php echo $page + 1 < $pnum? $page + 1: $pnum; ? " rel="external nofollow"  下一页</a