unique

返回集合中所有唯一的项目。返回的集合保留着原数组的键，所以在这个例子中，我们会使用 values 方法来把键重置为连续编号的索引。

collect([1, 1, 2, 2, 3, 4, 2])->unique();

// [ 0 => 1, 2 => 2, 4 => 3, 5 => 4]

自定义键

处理嵌套数组或对象时，可以指定用来决定唯一性的键

collect([
  ['name' => 'iPhone 6', 'brand' => 'Apple', 'type' => 'phone'],
  ['name' => 'iPhone 5', 'brand' => 'Apple', 'type' => 'phone'],
  ['name' => 'Apple Watch', 'brand' => 'Apple', 'type' => 'watch'],
  ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'],
  ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watch'],
])->unique('brand');

/*
[
    ["name" => "iPhone 6", "brand" => "Apple", "type" => "phone"],
    ["name" => "Galaxy S6", "brand" => "Samsung", "type" => "phone"]
]
*/

自定义回调

也可以传入自己的回调来确定项目的唯一性：

collect([
  ['name' => 'iPhone 6', 'brand' => 'Apple', 'type' => 'phone'],
  ['name' => 'iPhone 5', 'brand' => 'Apple', 'type' => 'phone'],
  ['name' => 'Apple Watch', 'brand' => 'Apple', 'type' => 'watch'],
  ['name' => 'Galaxy S6', 'brand' => 'Samsung', 'type' => 'phone'],
  ['name' => 'Galaxy Gear', 'brand' => 'Samsung', 'type' => 'watch'],
])->unique(fn ($item) => $item['brand'] . $item['type']);

/*
[
    ["name" => "iPhone 6", "brand" => "Apple", "type" => "phone"],
    ["name" => "Apple Watch", "brand" => "Apple", "type" => "watch"],
    ["name" => "Galaxy S6", "brand" => "Samsung", "type" => "phone"],
    ["name" => "Galaxy Gear", "brand" => "Samsung", "type" => "watch"]
]
*/

在检查项目值时 unique 方法使用的是「宽松」比较，意味着具有整数值的字符串将被视为等于相同值的整数。

使用 uniqueStrict 可以进行「严格」比较 。

相关方法

• uniqueStrict