如何使多维数组独一无二？

Question

我有一个多维数组设置,如下所示:

array(
  [0]=>
  array(
    ["name"]=> "Foo"
    ["slug"]=> "Bar"
  )
  [1]=>
  array(
    ["name"]=> "Foo"
    ["slug"]=> "Bar"
  )
  [2]=>
  array(
    ["name"]=> "Test 1"
    ["slug"]=> "test-1"
  )
  [3]=>
  array(
    ["name"]=> "Test 2"
    ["slug"]=> "test-2"
  )
  [4]=>
  array(
    ["name"]=> "Test 3"
    ["slug"]=> "test-3"
  )
)

在"name"中搜索区域中的重复值并删除它们的最佳方法是什么,以便多维数组中的每个值都是唯一的？

提前致谢!

Answer 1

您可以使用关联数组.

$temp_array = array();
foreach ($array as &$v) {
    if (!isset($temp_array[$v['name']]))
        $temp_array[$v['name']] =& $v;
}

这将创建一个临时数组,$v['name']用作键.如果已存在具有相同键的元素,则不会将其添加到临时数组中.

您可以使用将关联数组转换回顺序数组

$array = array_values($temp_array);

示例代码和输出:http://codepad.org/zHfbtUrl

Answer 2

由于每个人都给出了替代方案,这里是解决问题的方法.有时我们必须使用我们拥有的数据,而不是按照我们喜欢的方式重新安排.话虽这么说,这将从数组中删除所有重复的后续条目.

$array = Array(
  Array(
    'name'  => 'Test 3',
    'slug'  => 'test-3'
  ),
  Array(
    'name'  => 'Foo',
    'slug'  => 'Bar'
  ),
  Array(
    'name'  => 'Foo',
    'slug'  => 'Bar'
  ),
  Array(
    'name'  => 'Test 1',
    'slug'  => 'test-1'
  ),
  Array(
    'name'  => 'Test 2',
    'slug'  => 'test-2'
  ),
  Array(
    'name'  => 'Test 3',
    'slug'  => 'test-3'
  ),
);
var_dump($array);

for ($e = 0; $e < count($array); $e++)
{
  $duplicate = null;
  for ($ee = $e+1; $ee < count($array); $ee++)
  {
    if (strcmp($array[$ee]['name'],$array[$e]['name']) === 0)
    {
      $duplicate = $ee;
      break;
    }
  }
  if (!is_null($duplicate))
    array_splice($array,$duplicate,1);
}
var_dump($array);

这将是这样的:

array(6) {
  [0]=>
  array(2) {
    ["name"]=>
    string(6) "Test 3"
    ["slug"]=>
    string(6) "test-3"
  }
  [1]=>
  array(2) {
    ["name"]=>
    string(3) "Foo"
    ["slug"]=>
    string(3) "Bar"
  }
  [2]=>
  array(2) {
    ["name"]=>
    string(3) "Foo"
    ["slug"]=>
    string(3) "Bar"
  }
  [3]=>
  array(2) {
    ["name"]=>
    string(6) "Test 1"
    ["slug"]=>
    string(6) "test-1"
  }
  [4]=>
  array(2) {
    ["name"]=>
    string(6) "Test 2"
    ["slug"]=>
    string(6) "test-2"
  }
  [5]=>
  array(2) {
    ["name"]=>
    string(6) "Test 3"
    ["slug"]=>
    string(6) "test-3"
  }
}
array(4) {
  [0]=>
  array(2) {
    ["name"]=>
    string(6) "Test 3"
    ["slug"]=>
    string(6) "test-3"
  }
  [1]=>
  array(2) {
    ["name"]=>
    string(3) "Foo"
    ["slug"]=>
    string(3) "Bar"
  }
  [2]=>
  array(2) {
    ["name"]=>
    string(6) "Test 1"
    ["slug"]=>
    string(6) "test-1"
  }
  [3]=>
  array(2) {
    ["name"]=>
    string(6) "Test 2"
    ["slug"]=>
    string(6) "test-2"
  }
}

Answer 3

$array = array(
    0 => array(
        "name"=> "Foo",
        "slug"=> "Bar"
    ),
    1 => array(
        "name"=> "Foo",
        "slug"=> "Bar"
    ),
    2 => array(
        "name"=> "Test 1",
        "slug"=> "test-1"
    ),
    3 => array(
        "name"=> "Test 2",
        "slug"=> "test-2"
    ),
    4 => array(
        "name"=> "Test 3",
        "slug"=> "test-3"
    )
);



function array_unique_by_key (&$array, $key) {
    $tmp = array();
    $result = array();
    foreach ($array as $value) {
        if (!in_array($value[$key], $tmp)) {
            array_push($tmp, $value[$key]);
            array_push($result, $value);
        }
    }
    return $array = $result;
}

array_unique_by_key($array, "name");