PHP array_unique implements two-dimensional array deduplication

array_unique The function can be used to handle duplicates. It has this function. Let’s take a look at the use of array_unique in PHP Two-dimensional array deduplication processing example.

php version 5.2.9 adds array_unique support for multi-dimensional arrays. When processing multi-dimensional arrays, you need to set sort_flagsParameters

Duplication of one-dimensional arrays Item:

Just use the array_unique function. The usage example is as follows:

The code is as follows

The result is as follows:

Array ( [0] => apple [1] => banana [2] => pear [4] => wail [5] => watermalon )

Two-dimensional array deduplication Item

The code is as follows

For example:

$result = array(
0=>array('a'=>1,'b '=>'Hello'),
1=>array('a'=>1,'b'=>'other'),
2=>array('a'= >1,'b'=>'other'),
);

is processed into

$result = array(
0=>array('a'=>1,'b'=>'Hello'),
1=>array('a'=>1,'b'=>' other')
);

Usage method

array_unique($result, SORT_REGULAR);

Duplicates of two-dimensional arrays:

For two-dimensional arrays, we will discuss it in two situations. One is because the value of a certain key name cannot be repeated, and duplicates are deleted; the other is because the internal one-dimensional The arrays cannot be exactly the same, and duplicates are deleted. The following is an example:

Because the value of a certain key name cannot be duplicated, duplicates are deleted

The PHP code is as follows

 $v) {
    if (in_array($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]);
    } else {
      $tmp_arr[] = $v[$key];
    }
  }
  sort($arr); //sort函数对数组进行排序
  return $arr;
}

$aa = array(
  array('id' => 123, 'name' => '张三'),
  array('id' => 123, 'name' => '李四'),
  array('id' => 124, 'name' => '王五'),
  array('id' => 125, 'name' => '赵六'),
  array('id' => 126, 'name' => '赵六')
);
$key = 'id';
assoc_unique(&$aa, $key);
print_r($aa);
?>

The displayed result is:

Array ( [0] => Array ( [id] => 123 [name] => 张三 ) [1] => Array ( [id] => 124 [name] => 王五 ) [2] => Array ( [id] => 125 [name] => 赵六 ) [3] => Array ( [id] => 126 [name] => 赵六 ) )

Because the internal one-dimensional arrays cannot be exactly the same, and duplicates are deleted

The code is as follows

 $v) {
    $temp[$k] = explode(",", $v);//再将拆开的数组重新组装
  }
  return $temp;
}
$aa = array(
  array('id' => 123, 'name' => '张三'),
  array('id' => 123, 'name' => '李四'),
  array('id' => 124, 'name' => '王五'),
  array('id' => 123, 'name' => '李四'),
  array('id' => 126, 'name' => '赵六')
);
$bb = array_unique_fb($aa);
print_r($bb)
?>

The displayed result is:

Array ( [0] => Array ( [0] => 123 [1] => 张三 ) [1] => Array ( [0] => 123 [1] => 李四 ) [2] => Array ( [0] => 124 [1] => 王五 ) [4] => Array ( [0] => 126 [1] => 赵六 ) )

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