using System; using System.Collections.Generic; using System.Linq; public class MainClass { public static void Main() { int[] numbers = { 10, 9, 8, 7, 6 }; int count = numbers.Count(); int min = numbers.Min(); } }
LINQ
Count with string operator
using System; using System.Linq; using System.Collections; using System.Collections.Generic; public class MainClass { public static void Main() { string[] presidents = {"G", "H", "a", "H", "over", "Jack"}; int count = presidents.Count(s => s.StartsWith("H")); Console.WriteLine(count); } }
Count with string value
using System; using System.Linq; using System.Collections; using System.Collections.Generic; public class MainClass { public static void Main() { string[] presidents = {"G", "H", "a", "H", "over", "Jack"}; int count = presidents.Count(); Console.WriteLine(count); } }
A query to extract strings containing the letter “a”, sorted by length and converted to uppercase
using System; using System.Collections.Generic; using System.Linq; class LinqDemo { static void Main() { string[] names = { "J", "P", "G", "Pa" }; IEnumerable<string> query = from n in names where n.Contains("a") orderby n.Length select n.ToUpper(); foreach (string name in query) Console.Write(name + "/"); } }
Contains with IEqualityComparer
using System; using System.Linq; using System.Collections; using System.Collections.Generic; public class MyStringifiedNumberComparer : IEqualityComparer<string> { public bool Equals(string x, string y) { return (Int32.Parse(x) == Int32.Parse(y)); } public int GetHashCode(string obj) { return Int32.Parse(obj).ToString().GetHashCode(); } } public class MainClass { public static void Main() { string[] stringifiedNums = {"001", "49", "017", "0080", "00027", "2" }; bool contains = stringifiedNums.Contains("2",new MyStringifiedNumberComparer()); Console.WriteLine(contains); } }
Contains with predicate returned false
using System; using System.Linq; using System.Collections; using System.Collections.Generic; public class MainClass { public static void Main() { string[] presidents = {"A", "H", "a", "H", "over", "Jack"}; bool contains = presidents.Contains("G"); Console.WriteLine(contains); } }
Use Contains to check the existance of an element
using System; using System.Collections; using System.Collections.Generic; using System.Text; using System.Linq; public class MainClass{ public static void Main(){ int[] numbers = { 2, 6, 1, 56, 102 }; Console.WriteLine("Is there the number 102?"); Console.Write(numbers.Contains(102) ? "Yes, there is" : "No, there isn't"); } }