public static void PruebaOfType()
{
ArrayList arraylist = new ArrayList();
arraylist.Add("test");
arraylist.Add("asd");
arraylist.Add("fds");
arraylist.Add("qwer");
arraylist.Add(2);
arraylist.Add(4);
var nro = arraylist.OfType <int>(); //Guarda en la variable nro todos los INT del arraylist
List <IActividad> eventos = new List <IActividad>();
// eventos.Add(new Actividad());
eventos.Add(new Tarea());
}
public static void PruebaOfType()
{ //arraylist : coleccion no generica que puede tener cualquier cosa dentro
ArrayList arrayList = new ArrayList();
arrayList.Add("test");
arrayList.Add("gabriel");
arrayList.Add(1);
arrayList.Add(2);
//me dan todos los que sean int //oftype es un filtrado
var numeros = arrayList.OfType <int>();
List <IActividad> eventos = new List <IActividad>();
//agrego a eventos
eventos.Add(new Actividad());
eventos.Add(new Tarea());
// solo guardo las que son del tipo tarea. aplico filtro sobre tipo de datos
var tareas = eventos.OfType <Tarea>();
}
public FirstTask()
{
IList <People> People_list = new List <People>
{
new People()
{
id = 1, FIO = "Ivan", salary = 1000, age = 22
},
new People()
{
id = 2, FIO = "Alexandr", salary = 1000, age = 24
},
new People()
{
id = 3, FIO = "Dmitry", salary = 4000, age = 34
},
new People()
{
id = 4, FIO = "Artem", salary = 4000, age = 33
},
new People()
{
id = 5, FIO = "Alexey", salary = 5000, age = 40
},
};
IList <Purchases> Purchases_list = new List <Purchases>
{
new Purchases()
{
id = 1, product_name = "product_1", units_amount = 3, cost = 100, people_id = 1
},
new Purchases()
{
id = 2, product_name = "product_2", units_amount = 4, cost = 200, people_id = 2
},
new Purchases()
{
id = 3, product_name = "product_3", units_amount = 5, cost = 300, people_id = 3
},
new Purchases()
{
id = 4, product_name = "product_4", units_amount = 2, cost = 150, people_id = 4
},
new Purchases()
{
id = 5, product_name = "product_5", units_amount = 2, cost = 150, people_id = 5
},
};
ArrayList test_list = new ArrayList()
{
new Purchases()
{
id = 1, product_name = "product_1", units_amount = 3, cost = 100, people_id = 1
},
new Purchases()
{
id = 2, product_name = "product_2", units_amount = 4, cost = 200, people_id = 2
},
new Purchases()
{
id = 3, product_name = "product_3", units_amount = 5, cost = 300, people_id = 3
},
new Purchases()
{
id = 4, product_name = "product_4", units_amount = 2, cost = 150, people_id = 4
},
new Purchases()
{
id = 5, product_name = "product_5", units_amount = 2, cost = 150, people_id = 5
},
new People()
{
id = 1, FIO = "Ivan", salary = 1000, age = 22
},
};
// Вывод всех значений
foreach (var i in People_list)
{
Console.WriteLine("id = " + i.id + " | FIO = " + i.FIO + " | salary = " + i.salary
+ " | age = " + i.age);
}
Console.WriteLine();
// 1. Пукупки, стоимость которых больше среднего арифметического (использование переменной диапозона let)
Console.WriteLine("1. Запрос: ");
var _1result = from c in Purchases_list
let avg_limit = (from g in Purchases_list
select g.units_amount * g.cost).Average()
where c.units_amount * c.cost > avg_limit
select c.product_name;
foreach (var i in _1result)
{
Console.WriteLine(i);
}
Console.WriteLine();
// 2. Группы по зарплате с максимальным возрастом в каждой (группировка)
Console.WriteLine("2. Запрос: ");
var group_example = from c in People_list
group c by c.salary into new_group
select new
{
first_coloumn = new_group.Key,
second_column = new_group.Count(),
Persons = from new_var in new_group
let inner_max_age = (from new_var_2 in new_group
select new_var_2.age).Max()
where new_var.age == inner_max_age
select new_var
};
foreach (var i in group_example)
{
Console.WriteLine("salary = {0} count = {1}", i.first_coloumn, i.second_column);
foreach (People inner_var in i.Persons)
{
Console.WriteLine(inner_var.FIO);
}
}
Console.WriteLine();
// 3. Запрос с OfType
Console.WriteLine("3. Запрос: ");
var _3result = test_list.OfType <Purchases>();
foreach (Purchases i in _3result)
{
Console.WriteLine(i.product_name);
}
Console.WriteLine();
// 4. Имена - возраста работников (двойная сортировка)
Console.WriteLine("4. Запрос: ");
var _4result = from c in People_list
orderby c.salary, c.age descending
select c;
foreach (var i in _4result)
{
Console.WriteLine(i.FIO + " has salary = " + i.salary + " with age = " + i.age);
}
Console.WriteLine();
// 5. Запрос с join (человек, совершивший самую дорогую покупку)
Console.WriteLine("5. Запрос: ");
var _6result = from c in People_list
join c1 in Purchases_list on c.id equals c1.people_id
let avg_limit = (from g in Purchases_list
select g.units_amount * g.cost).Max()
where c1.cost * c1.units_amount == avg_limit
select new { name = c.FIO, purchase_summ = c1.units_amount * c1.cost };
foreach (var item in _6result)
{
Console.WriteLine(item.name + " " + item.purchase_summ);
}
}