PHP two-dimensional array deduplication example analysis

This article analyzes the method of deduplication of two-dimensional arrays in PHP through examples. Share it with everyone for your reference, the details are as follows:

Everyone knows that one-dimensional arrays can reuse the system function array_unique($arr)

And today I used a two-dimensional array, and I also want to reuse it. Baidu has a lot of them. Convert 2D to 1D and then use array_unique($arr)

I was very annoyed by it, so I decided to write one myself. Simpler and easier to understand than his, record it for later use

header('content-type:text/html;charset=utf8');
$arr = array(
array('id'=>1,'psid'=>'P101','fullname'=>'课程计划全称 101','userid'=>4),
array('id'=>1,'psid'=>'P101','fullname'=>'课程计划全称 101','userid'=>3),
array('id'=>1,'psid'=>'P101','fullname'=>'课程计划全称 101','userid'=>3),
array('id'=>1,'psid'=>'P101','fullname'=>'课程计划全称 101','userid'=>2),
array('id'=>2,'psid'=>'P102','fullname'=>'新课程计划','userid'=>4),
array('id'=>2,'psid'=>'P102','fullname'=>'新课程计划','userid'=>3),
array('id'=>2,'psid'=>'P102','fullname'=>'新课程计划','userid'=>3),
array('id'=>2,'psid'=>'P102','fullname'=>'新课程计划','userid'=>2)
);
$arr = er_array_unique($arr);
foreach($arr as $v){
  echo &#39;id: &#39;.$v[&#39;id&#39;].&#39;psid: &#39;.$v[&#39;psid&#39;].&#39; fullname: &#39;.$v[&#39;fullname&#39;].&#39; userid: &#39;.$v[&#39;userid&#39;].&#39;<br/>&#39;;
}
//二维数组简单去重
function er_array_unique($arr){
  $newarr = array();
  if(is_array($arr)){
    foreach($arr as $v){
      if(!in_array($v,$newarr,true)){
        $newarr[] = $v;
      }
    }
  }else{
     return false;
  }
  return $newarr;
}

Print result:

id: 1psid: P101 fullname: 课程计划全称 101 userid: 4
id: 1psid: P101 fullname: 课程计划全称 101 userid: 3
id: 1psid: P101 fullname: 课程计划全称 101 userid: 2
id: 2psid: P102 fullname: 新课程计划 userid: 4
id: 2psid: P102 fullname: 新课程计划 userid: 3
id: 2psid: P102 fullname: 新课程计划 userid: 2

Note: in_array($need,$arr,$strict)

in this method Prior to PHP version 4.2.0, $need was not allowed to be an array. If $stric is true, it will strictly match the types to be found in $need and $arr