PHP中二维数组排序问题
PHP中二维数组排序,可以使用PHP内置函数uasort()
【使用用户自定义的比较函数对数组中的值进行排序并保持索引关联】
回调函数如下:注意回调函数的返回值是负数或者是false的时候,表示回调函数的第一个参数在前,第二个参数在后排列
$person = array( array('num'=>'001','id'=>6,'name'=>'zhangsan','age'=>21), array('num'=>'001','id'=>7,'name'=>'ahangsan','age'=>23), array('num'=>'003','id'=>1,'name'=>'bhangsan','age'=>23), array('num'=>'001','id'=>3,'name'=>'dhangsan','age'=>23), );
//负数或者false表示第一个参数应该在前 function sort_by_name($x,$y){ return strcasecmp($x['name'],$y['name']); }使用如下:
uasort($person,'sort_by_name');
下面给出一个二维数组排序的方法,供参考和面试使用:
//$array 要排序的数组 //$row 排序依据列 //$type 排序类型[asc or desc] //return 排好序的数组 function array_sort($array,$row,$type){ $array_temp = array(); foreach($array as $v){ $array_temp[$v[$row]] = $v; } if($type == 'asc'){ ksort($array_temp); }elseif($type='desc'){ krsort($array_temp); }else{ } return $array_temp; }
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这里顺便说一下PHP排序的几个函数
【sort 对数组排序】一般适用于一维索引数组,不会保持索引
【rsort 对数组逆向排序】 和sort用法一致
【asort 对数组进行排序并保持索引关系】对值进行排序,一般适用于一维数组,保持索引关系
【arsort 对数组进行逆向排序并保持索引关系】和asort用法一致
【ksort 对数组按照键名排序】
【krsort 对数组按照键名逆向排序】
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