laravel 集合常用方法

laravel 集合常用方法

all()

//创建集合
$collection = collect(['abc','fengge','wuge']);

//以底层数组形式输出
return $collection;//["abc","fengge","wuge"]
return $collection->all();["abc","fengge","wuge"]

map

//map 方法，类似访问器，可修改输出
return $collection->reject(function ($value,$key){
            return  $value === 'abc';
        })
//["abc-0","fengge-1","wuge-2"]

reject

//支持链式，reject移出true 的值
return $collection->reject(function ($value,$key){
            return  $value === 'abc';
        })
 //{"1":"fengge","2":"wuge"}
 
 //支持链式，reject移出非true 的值
return $collection->reject(function ($value,$key){
            return  $value != 'abc';
        })
 //["abc"]
 

filter

//filter筛选为true 的值，和reject 相反
return $collection->filter(function ($value,$key){
            return  $value === 'abc';
        })
 //["abc"]

search

//search找到后返回key，找不到返回false
return $collection->search('abc');

each

//迭代输
$collection->each(function ($item, $key) { echo $item; echo '--';});
//abc--fengge--wuge--

chunk

//集合的分割
return $collection->chunk(2);
[["abc","fengge"],{"2":"wuge"}]

自定义方法

//use Illuminate\Support\Collection;
//果三十多个方法都没有你要的，还可以自定义方法，比如说所有英文大写； 
$collection = collect(['Mr.Zhang', '李四', '王五', null]);
Collection::macro('toUpper', function () { //dd($this); 
	return $this->map(function ($value) { 
		return strtoupper($value); 
	});
});
return $collection->toUpper();
//["MR.ZHANG","\u674e\u56db","\u738b\u4e94",""]

avg

//返回平均值 
$collection = collect([1, 2, 3, 4]); 
return $collection->avg(); //2.5


//返回分组平均值 
$collection = collect([['男'=>1], ['女'=>1], ['男'=>3]]);
return $collection->avg('男');
//2

count

//返回集合总数； 
$collection = collect([1, 2, 3, 4]); 
return $collection->count()
//4

PS：相关的还有 sum()、min()、max()等统计

countBy()

//返回数值出现的次数或回调函数指定值出现的次数

//值出现的次数 
$collection = collect([1, 2, 2, 3, 4, 4, 4]); 
return $collection->countBy();
//{"1":1,"2":2,"3":1,"4":3}

//回调搜索相同指定片段的值的次数 
$collection = collect(['xiaoxin@163.com', 'yihu@163.com', 'xiaoying@qq.com']);
return $collection->countBy(function ($value) { 
	return substr(strrchr($value, '@'), 1); 
});
//{"163.com":2,"qq.com":1}

diff()

//返回集合数组之间不相同的部分，组合新的集合；

//diff返回两个集合中不相同的 
$collection = collect([1, 2, 3, 4, 5]); 
return $collection->diff([3, 5]);
//{"0":1,"1":2,"3":4}

duplicates()

//返回重复的值；
$collection = collect([1, 2, 2, 3, 4, 5, 5, 6]);
return $collection->duplicates(); //严格派生方法：duplicatesStrict()
{"2":2,"6":5}

flatten()

//将多维数组转换为一维
$collection = collect(['name'=>'Mr.Lee', 'details'=>['gender'=>'男', 'age'=>100]]);
return $collection->flatten();
//["Mr.Lee","\u7537",100]

get()

//get()通过键名找值
$collection = collect(['name'=>'Mr.Lee', 'gender'=>'男']); 
return $collection->get('name');
//Mr.Lee

has()

//判断集合中是否存在指定键；
$collection = collect(['name'=>'Mr.Lee', 'gender'=>'男']); 
return $collection->has('name');
//1

pop()

移出集合中最后一个值
$collection = collect([1, 2, 3, 4, 5]);
$collection->pop(); 
return $collection;
//[1,2,3,4]

PS：相关的还有 pull()、push()、put()方法

slice()

//返回指定值后续的集合； 
$collection = collect([1, 2, 3, 4, 5]); 
return $collection->slice(3);//{"3":4,"4":5}

sort()

//返回指定值后续的集合； 
$collection = collect([3, 1 , 5, 2, 7]); 
return $collection->sort()->values(); //需要配合 values()方法
//[1,2,3,5,7]

PS：类似的有 sortBy()、sortByDesc()、sortKeys()等

where()

//系列方法，和数据库条件一样； 
$collection = collect([ ['name'=>'Mr.Lee', 'gender'=>'男'], ['name'=>'Miss.Zhang', 'gender'=>'女'] ]); 
return $collection->where('name', 'Mr.Lee');
//[{"name":"Mr.Lee","gender":"\u7537"}]

模型集合

map()

 //通过它可以实现类似访问器一样对字段进行处理的效果
 $users = User::get();
 $women = $users->map(function ($user) { 
	$user->email = strtoupper($user->email); return $user; 
 });
 return $women;//[[XIAOXIN@163.COM]]
 
 PS：数据集合支持连缀操作，和数据库连缀一样；

reject

使用 reject()方法，可以获取条件之外的数据内容； 
$women = $users->reject(function ($user) { 
	return $user->gender != '女'; 
})
->map(function ($user) { return $user; });
//返回gender 女的数据

contains

//判断集合中是否包含指定的模型实例 
return $users->contains(19);//1 
return $users->contains(User::find(19));//1

diff

 //返回不在集合中的所有模型 
 return $users->diff(User::whereIn('id', [19,20,21])->get()); 
 

except

//返回给定主键外的所有模型 
return $users->except([19,20,21]); 

find

//集合也有find 方法 
return $users->find(19); 
//{"id":19,"username":"\u8721\u7b14\u5c0f\u65b0","password":"123","gender":"\u7537","email":"[xiaoxin@163.com]","price":"60.00","details":"123","uid":1001,"status":-1,"list":"{\"id\": 19, \"uid\": 1010}","deleted_at":null,"created_at":"2016-06-27T16:45:26.000000Z","updated_at":"2016-06-27T16:45:26.000000Z","info":"\u8721\u7b14\u5c0f\u65b0-xiaoxin@163.com"}

count

//返回集合的数量 
return $users->count(); //20

modelKeys

//返回所有模型的主键 return $users->modelKeys();
//[19,20,21,24,25,26,27,29,76,79,80,99,304,305,308,309,312,313,314,315]

only

//返回主键的所有模型
return $users->only([19,20,21]); ///这几个主键的模型

unique

//返回集合中的唯一模型 唯一数据
return $users->unique();