PHP二维数组去重的方法（保留各个键值的同时去除重复的项）-- 二维数组的唯一性

对于如下二维数组，要求对其进行去重：

$arr = array(
          "0"=>array(
                    "name"=>"james",
                    "age"=>30,
                    ),
          "1"=>array(
                    "name"=>"susu",
                    "age"=>26,
                    ),
          "2"=>array(
                    "name"=>"james",
                    "age"=>30,
                    ),
          "new"=>array(
                    "name"=>"kube",
                    "age"=>37,
                    ),
          "list"=>array(
                    "name"=>"kube",
                    "age"=>27,
                    ),
          );

1、 二维数组内部的一维数组中的值不能完全相同，删除其中重复的项：

代码如下：

<?php
$arr = array(
          "0"=>array(
                   "name"=>"james",
                   "age"=>30,
                   ),
          "1"=>array(
                   "name"=>"susu",
                   "age"=>26,
                   ),
           "2"=>array(
                   "name"=>"james",
                   "age"=>30,
                   ),
           "new"=>array(
                   "name"=>"kube",
                   "age"=>37,
                   ),
           "list"=>array(
                   "name"=>"kube",
                   "age"=>27,
                   ),
           );
printf("Before tranform the array:<br>");   //输出原来的数组
print_r($arr);
echo "<br/>";
function more_array_unique($arr=array()){
    foreach($arr[0] as $k => $v){
        $arr_inner_key[]= $k;   //先把二维数组中的内层数组的键值记录在在一维数组中
    }
    foreach ($arras $k => $v){
        $v =join(",",$v);    //降维 用implode()也行
        $temp[$k] =$v;      //保留原来的键值 $temp[]即为不保留原来键值
    }
    printf("After split the array:<br>");
    print_r($temp);    //输出拆分后的数组
    echo"<br/>";
    $temp =array_unique($temp);    //去重：去掉重复的字符串
    foreach ($tempas $k => $v){
        $a = explode(",",$v);   //拆分后的重组 如：Array( [0] => james [1] => 30 )
        $arr_after[$k]= array_combine($arr_inner_key,$a);  //将原来的键与值重新合并
    }
    //ksort($arr_after);//排序如需要：ksort对数组进行排序(保留原键值key) ,sort为不保留key值
    return$arr_after;
}
    $arr_new = more_array_unique($arr);  //调用去重函数
    printf("Duplicate removal of the array:<br>");
    print_r($arr_new);
echo "<br/>";
?>

输出结果：

Before tranform the array:   //原来数组
Array ( [0] => Array ( [name] => james [age] => 30 ) [1] => Array ([name] => susu [age] => 26 ) [2] => Array ( [name] => james [age]=> 30 ) [new] => Array ( [name] => kube [age] => 37 ) [list] =>Array ( [name] => kube [age] => 27 ) ) 
After split the array:  //拆分后数组
Array ( [0] => james,30 [1] => susu,26 [2] => james,30 [new] =>kube,37 [list] => kube,27 ) 
Duplicate removal of thearray:  //去重后数组
Array ( [0] => Array ( [name] => james [age] => 30 ) [1] => Array ([name] => susu [age] => 26 ) [new] => Array ( [name] => kube [age]=> 37 ) [list] => Array ( [name] => kube [age] => 27 ) ) 

2、 二维数组内部的一维数组因某一个键值不能相同，删除重复项：

/*针对某一个键值来进行去重*/

<?php
$arr= array(……);  //同上的二维数组
functionsecond_array_unique_bykey($arr, $key){
    $tmp_arr = array();
    foreach($arr as $k => $v)
    {
        if(in_array($v[$key], $tmp_arr))   //搜索$v[$key]是否在$tmp_arr数组中存在，若存在返回true
        {
            unset($arr[$k]); //销毁一个变量  如果$tmp_arr中已存在相同的值就删除该值
        }
        else {
            $tmp_arr[$k] = $v[$key];  //将不同的值放在该数组中保存
        }
   }
   //ksort($arr); //ksort函数对数组进行排序(保留原键值key)  sort为不保留key值
    return $arr;
   }
   $key ="name";
   $arr_key = second_array_unique_bykey($arr,$key);
   printf("As for the givenkey->%s:<br>",$key);
   print_r($arr_key);
   echo "<br/>";
?>

输出结果：

As for the given key->name:
Array ( [0] => Array ( [name] => james [age] => 30 ) [1] => Array ([name] => susu [age] => 26 ) [new] => Array ( [name] => kube [age]=> 37 ) )