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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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