Csharp/CSharp Tutorial/LINQ/Max

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Get the Min and max value from a query

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;
using System.Reflection;
class Salary {
    int _id;
    int _year;
    double _salary;
    public int ID {
        get { return _id; }
        set { _id = value; }
    }
    public int Year {
        get { return _year; }
        set { _year = value; }
    }
    public double SalaryPaid {
        get { return _salary; }
        set { _salary = value; }
    }
}
class Employee {
    int _id;
    int _idRole;
    string _lastName;
    string _firstName;
    public int ID {
        get { return _id; }
        set { _id = value; }
    }
    public int IDRole {
        get { return _idRole; }
        set { _idRole = value; }
    }
    public string LastName {
        get { return _lastName; }
        set { _lastName = value; }
    }
    public string FirstName {
        get { return _firstName; }
        set { _firstName = value; }
    }
}
class Role {
    int _id;
    string role;
    public int ID {
        get { return _id; }
        set { _id = value; }
    }
    public string Role {
        get { return role; }
        set { role = value; }
    }
}
public class MainClass {
    public static void Main() {
        List<Employee> people = new List<Employee> {
               new Employee { ID = 1, IDRole = 1, LastName = "A", FirstName = "B"},
               new Employee { ID = 2, IDRole = 2, LastName = "G", FirstName = "T"},
               new Employee { ID = 3, IDRole = 2, LastName = "G", FirstName = "M"},
               new Employee { ID = 4, IDRole = 3, LastName = "C", FirstName = "G"}
            };
        List<Role> roles = new List<Role> {
               new Role { ID = 1, Role = "Manager" },
               new Role { ID = 2, Role = "Developer" }
            };
        List<Salary> salaries = new List<Salary> {
               new Salary { ID = 1, Year = 2004, SalaryPaid = 10000.00 },
               new Salary { ID = 1, Year = 2005, SalaryPaid = 15000.00 },
               new  Salary { ID = 1, Year = 2005, SalaryPaid = 15000.00 }
            };
        var query = from p in people
                    join s in salaries on p.ID equals s.ID
                    where p.ID == 1
                    select s.SalaryPaid;
        Console.WriteLine("Minimum Salary:");
        Console.Write(query.Min());
        Console.WriteLine("Maximum Salary:");
        Console.Write(query.Max());
    }
}

Grouped Max

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
    public static void Main() {
        List<Product> products = GetProductList();
        var categories =
           from p in products
           group p by p.Category into g
           select new { Category = g.Key, MostExpensivePrice = g.Max(p => p.UnitPrice) };
        Console.Write(categories);
    }
    static List<Product> GetProductList() {
        List<Product> empTree = new List<Product>();
        empTree.Add(new Product { ProductName = "A", Category = "O", UnitPrice = 12, UnitsInStock = 5, Total = 36, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        empTree.Add(new Product { ProductName = "B", Category = "O", UnitPrice = 2, UnitsInStock = 4, Total = 35, OrderDate = new DateTime(2005, 1, 1), Id = 2 });
        empTree.Add(new Product { ProductName = "C", Category = "O", UnitPrice = 112, UnitsInStock = 3, Total = 34, OrderDate = new DateTime(2005, 1, 1), Id = 3 });
        empTree.Add(new Product { ProductName = "D", Category = "O", UnitPrice = 112, UnitsInStock = 0, Total = 33, OrderDate = new DateTime(2005, 1, 1), Id = 4 });
        empTree.Add(new Product { ProductName = "E", Category = "O", UnitPrice = 1112, UnitsInStock = 2, Total = 32, OrderDate = new DateTime(2005, 1, 1), Id = 5 });
        empTree.Add(new Product { ProductName = "F", Category = "O", UnitPrice = 11112, UnitsInStock = 0, Total = 31, OrderDate = new DateTime(2005, 1, 1), Id = 6 });
        return empTree;
    }
    static List<Customer> GetCustomerList() {
        List<Product> empTree = new List<Product>();
        empTree.Add(new Product { ProductName = "A", Category = "O", UnitPrice = 12, UnitsInStock = 5, Total = 36, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        empTree.Add(new Product { ProductName = "B", Category = "O", UnitPrice = 2, UnitsInStock = 4, Total = 35, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        empTree.Add(new Product { ProductName = "C", Category = "O", UnitPrice = 112, UnitsInStock = 3, Total = 34, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        empTree.Add(new Product { ProductName = "D", Category = "O", UnitPrice = 112, UnitsInStock = 0, Total = 33, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        empTree.Add(new Product { ProductName = "E", Category = "O", UnitPrice = 1112, UnitsInStock = 2, Total = 32, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        empTree.Add(new Product { ProductName = "F", Category = "O", UnitPrice = 11112, UnitsInStock = 0, Total = 31, OrderDate = new DateTime(2005, 1, 1), Id = 1 });
        List<Customer> l = new List<Customer>();
        l.Add(new Customer { CompanyName = "A", Region = "R1", UnitsInStock = 1, Orders = empTree, CustomerId = 0 });
        l.Add(new Customer { CompanyName = "B", Region = "R2", UnitsInStock = 2, Orders = empTree, CustomerId = 1 });
        l.Add(new Customer { CompanyName = "C", Region = "R3", UnitsInStock = 3, Orders = empTree, CustomerId = 2 });
        l.Add(new Customer { CompanyName = "D", Region = "R4", UnitsInStock = 4, Orders = empTree, CustomerId = 3 });
        l.Add(new Customer { CompanyName = "E", Region = "R5", UnitsInStock = 5, Orders = empTree, CustomerId = 4 });
        return l;
    }
}
class Customer : IComparable<Customer> {
    public string CompanyName { get; set; }
    public string Region { get; set; }
    public List<Product> Orders { get; set; }
    public int UnitsInStock { get; set; }
    public int CustomerId { get; set; }
    public override string ToString() {
        return String.Format("Id: {0}, Name: {1}, Region: {3}", this.CustomerId, this.rupanyName, this.Region);
    }
    int IComparable<Customer>.rupareTo(Customer other) {
        if (other == null)
            return 1;
        if (this.CustomerId > other.CustomerId)
            return 1;
        if (this.CustomerId < other.CustomerId)
            return -1;
        return 0;
    }
}
class Product : IComparable<Product> {
    public string ProductName { get; set; }
    public string Category { get; set; }
    public int UnitPrice { get; set; }
    public int UnitsInStock { get; set; }
    public int Total { get; set; }
    public DateTime OrderDate { get; set; }
    public int Id { get; set; }
    public override string ToString() {
        return String.Format("Id: {0}, Name: {1} , Category: {3}", this.Id, this.ProductName, this.Category);
    }
    int IComparable<Product>.rupareTo(Product other) {
        if (other == null)
            return 1;
        if (this.Id > other.Id)
            return 1;
        if (this.Id < other.Id)
            return -1;
        return 0;
    }
}

Max on int array

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        int[] myInts = new int[] { 974, 2, 7, 1374, 27, 54 };
        int maxInt = myInts.Max();
        Console.WriteLine(maxInt);
    }
}

Max on object list

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class Employee {
    public int birthYear;
    public string firstName;
    public string lastName;
    public static Employee[] GetEmployees() {
        Employee[] actors = new Employee[] {
        new Employee { birthYear = 1964, firstName = "K", lastName = "R" },
        new Employee { birthYear = 1968, firstName = "O", lastName = "W" },
        new Employee { birthYear = 1960, firstName = "J", lastName = "S" },
        new Employee { birthYear = 1964, firstName = "S", lastName = "B" },
      };
        return (actors);
    }
}
public class MainClass {
    public static void Main() {
        int youngestEmployeeAge = Employee.GetEmployees().Max(a => a.birthYear);
        Console.WriteLine(youngestEmployeeAge);
    }
}

Max on Object list array

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class Employee {
    public int birthYear;
    public string firstName;
    public string lastName;
    public static Employee[] GetEmployees() {
        Employee[] actors = new Employee[] {
        new Employee { birthYear = 1964, firstName = "K", lastName = "R" },
        new Employee { birthYear = 1968, firstName = "O", lastName = "W" },
        new Employee { birthYear = 1960, firstName = "J", lastName = "S" },
        new Employee { birthYear = 1964, firstName = "S", lastName = "B" },
      };
        return (actors);
    }
}
public class MainClass {
    public static void Main() {
        string lastAlphabetically = Employee.GetEmployees().Max(a => a.lastName);
        Console.WriteLine(lastAlphabetically);
    }
}

Max on String array

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"G", "H", "H", "H", "H", "J"};
        string maxName = presidents.Max();
        Console.WriteLine(maxName);
    }
}

Numeric Aggregates: max

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
    class Program
    {
        static void Main(string[] args)
        {
            Random generator = new Random(0);
            int[] numbers = new int[1000];
            for (int i = 0; i < 1000; i++)
            {
                numbers[i] = generator.Next();
            }
            var queryResults = from n in numbers where n > 100 select n;
            Console.WriteLine("Max of Numbers > 100");
            Console.WriteLine(queryResults.Max());
        }
    }

uses Max to get the length of the longest word in a string array.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
    public static void Main() {
        string[] words = { "cherry", "apple", "blueberry" };
        int longestLength = words.Max(w => w.Length);
        Console.WriteLine("The longest word is {0} characters long.", longestLength);
    }
}

Using Max to get the highest number in an integer array.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class MainClass {
    public static void Main() {
        int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };
        int maxNum = numbers.Max();
        Console.WriteLine("The maximum number is {0}.", maxNum);
    }
}
Источник — «http://nfex.ru/index.php?title=Csharp/CSharp_Tutorial/LINQ/Max&oldid=6075»