二维数组比较的问题？

Question

$data = [
    ['foo' => 'bar', 'x' => 'foo'],
    ['foo' => 'bar1', 'x' => 'foo1'],
    ['foo' => 'bar', 'x' => 'foo2']
];

我需要把这个数组中的foo重复的数组删除，只保留下来一条就行。怎么做？

$data = [
    ['foo' => 'bar', 'x' => 'foo'],
    ['foo' => 'bar1', 'x' => 'foo1'],
];

Answer 1

//$arr = array_merge($data1,$data2);
//合并需要合并的俩个数组
  $key = 'foo';//去重条件
  $tmp_arr = array();//声明数组
  //var_dump($data);
 foreach($data 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($data[$k]);
   //删除掉数组（$arr）里相同ID的数组
  }
 else {
   $tmp_arr[] = $v[$key];
   //记录已有的id
  }
 }
var_dump($data);

Answer 2

        $tmp  = [];
        foreach ($data as $key => $datum) {
            if (in_array($datum['foo'], $tmp)) {
                unset($data[$key]);
                continue;
            }
            $tmp[] = $datum['foo'];
        }