php多维数组排序

　　数组

 array(11) {
   [0] => array(7) {
     ["food_id"] => string(2) "31"
     ["food_name"] => string(6) "啤酒"
     ["food_num"] => string(2) "22"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "1"
     ["x"] => int(2)
   }
   [1] => array(7) {
     ["food_id"] => string(2) "32"
     ["food_name"] => string(6) "红酒"
     ["food_num"] => string(2) "24"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "2"
     ["x"] => int(15)
   }
   [2] => array(7) {
     ["food_id"] => string(2) "33"
     ["food_name"] => string(6) "白酒"
     ["food_num"] => string(2) "12"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "3"
     ["x"] => int(0)
   }
   [3] => array(7) {
     ["food_id"] => string(2) "34"
     ["food_name"] => string(6) "拉菲"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "4"
     ["x"] => int(0)
   }
   [4] => array(7) {
     ["food_id"] => string(2) "35"
     ["food_name"] => string(8) "88拉菲"
     ["food_num"] => string(2) "24"
     ["foods_id"] => string(1) "8"
     ["foods_name"] => string(6) "红酒"
     ["ROW_NUMBER"] => string(1) "5"
     ["x"] => int(12)
   }
   [5] => array(7) {
     ["food_id"] => string(2) "36"
     ["food_name"] => string(9) "葡萄酒"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "8"
     ["foods_name"] => string(6) "红酒"
     ["ROW_NUMBER"] => string(1) "6"
     ["x"] => int(0)
   }
   [6] => array(7) {
     ["food_id"] => string(2) "37"
     ["food_name"] => string(9) "矿泉水"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "7"
     ["x"] => int(0)
   }
   [7] => array(7) {
     ["food_id"] => string(2) "38"
     ["food_name"] => string(6) "可乐"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "8"
     ["x"] => int(0)
   }
   [8] => array(7) {
     ["food_id"] => string(2) "39"
     ["food_name"] => string(6) "雪碧"
     ["food_num"] => string(2) "50"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "9"
     ["x"] => int(50)
   }
   [9] => array(7) {
     ["food_id"] => string(2) "40"
     ["food_name"] => string(9) "百岁山"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(2) "10"
     ["x"] => int(0)
   }
   [10] => array(7) {
     ["food_id"] => string(2) "41"
     ["food_name"] => string(6) "冰霜"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(2) "11"
     ["x"] => int(0)
   }
 }

　　方法：

 foreach ($food as $key => $row) {
     $id[$key]  = $row['x'];
 }
 array_multisort($id, SORT_DESC , $food);

　　结果：

 array(11) {
   [0] => array(7) {
     ["food_id"] => string(2) "39"
     ["food_name"] => string(6) "雪碧"
     ["food_num"] => string(2) "50"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "9"
     ["x"] => int(50)
   }
   [1] => array(7) {
     ["food_id"] => string(2) "32"
     ["food_name"] => string(6) "红酒"
     ["food_num"] => string(2) "24"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "2"
     ["x"] => int(15)
   }
   [2] => array(7) {
     ["food_id"] => string(2) "35"
     ["food_name"] => string(8) "88拉菲"
     ["food_num"] => string(2) "24"
     ["foods_id"] => string(1) "8"
     ["foods_name"] => string(6) "红酒"
     ["ROW_NUMBER"] => string(1) "5"
     ["x"] => int(12)
   }
   [3] => array(7) {
     ["food_id"] => string(2) "31"
     ["food_name"] => string(6) "啤酒"
     ["food_num"] => string(2) "22"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "1"
     ["x"] => int(2)
   }
   [4] => array(7) {
     ["food_id"] => string(2) "33"
     ["food_name"] => string(6) "白酒"
     ["food_num"] => string(2) "12"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "3"
     ["x"] => int(0)
   }
   [5] => array(7) {
     ["food_id"] => string(2) "34"
     ["food_name"] => string(6) "拉菲"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "4"
     ["x"] => int(0)
   }
   [6] => array(7) {
     ["food_id"] => string(2) "36"
     ["food_name"] => string(9) "葡萄酒"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "8"
     ["foods_name"] => string(6) "红酒"
     ["ROW_NUMBER"] => string(1) "6"
     ["x"] => int(0)
   }
   [7] => array(7) {
     ["food_id"] => string(2) "37"
     ["food_name"] => string(9) "矿泉水"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "7"
     ["x"] => int(0)
   }
   [8] => array(7) {
     ["food_id"] => string(2) "38"
     ["food_name"] => string(6) "可乐"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(1) "8"
     ["x"] => int(0)
   }
   [9] => array(7) {
     ["food_id"] => string(2) "40"
     ["food_name"] => string(9) "百岁山"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(2) "10"
     ["x"] => int(0)
   }
   [10] => array(7) {
     ["food_id"] => string(2) "41"
     ["food_name"] => string(6) "冰霜"
     ["food_num"] => string(1) "0"
     ["foods_id"] => string(1) "1"
     ["foods_name"] => string(6) "凉菜"
     ["ROW_NUMBER"] => string(2) "11"
     ["x"] => int(0)
   }
 }