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HomeBackend DevelopmentPHP TutorialPHP中array_slice函数用法实例详解_php技巧

本文详细介绍了array_slice函数的详细用法以及一些常用的array_slice实例程序,分享给大家供大家参考。具体分析如下:

array_slice() 函数在数组中根据条件取出一段值,并返回.

注释:如果数组有字符串键,所返回的数组将保留键名,参见例子 4.

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

函数在数组中根据条件取出一段值,并返回.

参数:

array  必需,规定输入的数组.

offset  必需,数值,规定取出元素的开始位置,如果是正数,则从前往后开始取,如果是负值,从后向前取offset 绝对值.

length  可选,数值,规定被返回数组的长度,如果是负数,则从后向前,选取该值绝对值数目的元素,如果未设置该值,则返回所有元素.

preserve 可选,可能的值:true – 保留键 false – 默认 – 重置键,当为0的时候,将里面的值赋值给一个新的变量,最后返回这个变量。

代码如下:

复制代码 代码如下:
    $arr = array(0,1,2,3,4);
    var_dump(array_slice($arr,0,2));
    
    echo "
";
    $arr2 = array('a'=>array('a','a','a'),'b'=>array('b','b','b'));
    var_dump(array_slice($arr2,0,1));
?>

返回的结果如下:
array(2) { [0]=> int(0) [1]=> int(1) } 
array(1) { ["a"]=> array(3) { [0]=> string(1) "a" [1]=> string(1) "a" [2]=> string(1) "a" } }

array_slice函数实现的分页方法非常好用,分享如下:

复制代码 代码如下:
//假定一个结果集二维数组:
   $arr = array(array('name'=> 'name1','sex' => 'sex1','job' => 'job1'),
              array('name'=> 'name2','sex' => 'sex2','job' => 'job2'),
              array('name'=> 'name3','sex' => 'sex3','job' => 'job3'),
              array('name'=> 'name4','sex' => 'sex4','job' => 'job4'),
              array('name'=> 'name5','sex' => 'sex5','job' => 'job5'),
              array('name'=> 'name6','sex' => 'sex6','job' => 'job6'),
              array('name'=> 'name7','sex' => 'sex7','job' => 'job7'),
              array('name'=> 'name8','sex' => 'sex8','job' => 'job8'),
              array('name'=> 'name9','sex' => 'sex9','job' => 'job9'),
              array('name'=> 'name10','sex' => 'sex10','job' => 'job10'),
              array('name'=> 'name11','sex' => 'sex11','job' => 'job11'),
              array('name'=> 'name12','sex' => 'sex12','job' => 'job12'),
     );
 
 //计算总记录条数
 $num = count($arr);
 //规定每页显示的条数
 $perpage = 3;
 //计算页数
 $pages = ceil($num/$perpage);
 //echo $num,$perpage,$pagecount;exit;
 if(is_numeric($_REQUEST['page']))
 {
  if($_REQUEST['page']    $page = 1;
  }elseif($_REQUEST['page']>$pages)
  {
   $page = $pages;
  }else{
  $page = $_REQUEST['page'];
   }
 }else{
  $page = 1;
 }
 $start = ($page-1)*$perpage;
 $newpage = array_slice($arr,$start,$perpage,true);
 //print_r($newpage);exit;
?>

 
 
 
 
 
 foreach($newpage as $k => $v)
{
?>
 
 
 
 
 
}
?>
name sex job

if($page>1){
 echo "首页";
 echo "上一页";
}
if($page {
 echo "下一页";
 echo "末页";
}
?>

希望本文所述对大家的PHP程序设计有所帮助。

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