Use the ContainsValue() method in C# to search for a value in a Dictionary.Create a Dictionary and add elements −Dictionary d = new Dictionary(); d.Add("keyboard", "One"); d.Add("mouse", "Two");Now, use the ContainsValue() method to find a particular value −d.ContainsValue("Two");The following is the complete code −Example Live Demousing System; using System.Collections.Generic; using System.Linq; class Program {    static void Main() {       Dictionary d = new Dictionary();       d.Add("keyboard", "One");       d.Add("mouse", "Two");       // search for a value       Console.WriteLine(d.ContainsValue("Two"));    } }OutputTrue

The ToDictionary method is an extension method in C# and converts a collection into Dictionary.Firstly, create a string array −string[] str = new string[] {"Car", "Bus", "Bicycle"};Now, use the Dictionary method to convert a collection to Dictionary −str.ToDictionary(item => item, item => true);Here is the complete code −Example Live Demousing System; using System.Collections.Generic; using System.Linq; class Demo {    static void Main() {       string[] str = new string[] {"Car", "Bus", "Bicycle"};       // key and value under ToDictionary       var d = str.ToDictionary(item => item, item => true);       foreach (var ele ... Read More

Set a list −List myList = new List() {    5,    10,    17,    19,    23,    33 };Let us say you need to find an element that is divisible by 2. For that, use the Find() method −int val = myList.Find(item => item % 2 == 0);Here is the complete code −Example Live Demousing System; using System.Collections.Generic; using System.Linq; class Demo {    static void Main() {       List myList = new List() {          5,          10,          17,          19,          23,          33       };       Console.WriteLine("List: ");       foreach(int i in myList) {          Console.WriteLine(i);       }       int val = myList.Find(item => item % 2 == 0);       Console.WriteLine("Element that divides by zero: "+val);    } }OutputList: 5 10 17 19 23 33 Element that divides by zero: 10

Use the Skip() method in C# to skip number of elements in an array.Let’s say the following is our array −int[] arr = { 10, 20, 30, 40, 50 };To skip the first two elements, use the Skip() method and add argument as 2 −arr.Skip(2);Let us see an example −Example Live Demousing System.IO; using System; using System.Linq; public class Demo {    public static void Main() {       int[] arr = { 10, 20, 30, 40, 50 };       Console.WriteLine("Initial Array...");       foreach (var res in arr) {          Console.WriteLine(res);     ... Read More

The All() extension method is part of the System.Linq namepspace. Using this method, you can check whether all the elements match a certain condition or not.Set an array −int[] arr = { 6, 7, 15, 40, 55 };The following is an example. It checks whether all the elements in the array is greater than and equal to 2 or not −arr.All(element => element > = 2);Here is the complete code −Example Live Demousing System; using System.Linq; class Program {    static void Main() {       int[] arr = { 6, 7, 15, 40, 55 };       bool res = arr.All(element => element >= 2);       Console.WriteLine(res);    } }OutputTrue

Use the Aggregate method in C# to perform mathematical operations such as Sum, Min, Max, Average, etc.Let us see an example to multiply array elements using Aggregate method.Here is our array −int[] arr = { 10, 15, 20 };Now, use Aggregate() method −arr.Aggregate((x, y) => x * y);Here is the complete code −Example Live Demousing System; using System.Linq; using System.IO; public class Demo {    public static void Main() {       int[] arr = { 10, 15, 20 };       // Multiplication       int res = arr.Aggregate((x, y) => x * y);       Console.WriteLine(res);    } }Output3000

With the TakeWhile() method, you can get methods by setting a condition base on Predicate.Firstly, declare and initialize an array −int[] arr = { 25, 40, 65, 70};Now, use the TakeWhile() method and predicate to get all the elements that are less than 30.var val = arr.TakeWhile(ele => ele < 30);Let us see the same example, wherein we have displayed the values less than 30 using Predicate −Example Live Demousing System; using System.Linq; using System.IO; public class Demo {    public static void Main() {       int[] arr = { 25, 40, 65, 70};       var val = arr.TakeWhile(ele => ele < 30);       foreach (int res in val) {          Console.WriteLine(res);       }    } }Output25

Firstly, use GetDrives to get the name of all the drives −var drv = DriveInfo.GetDrives();Loop through to get the name of all the drives on the system −foreach (DriveInfo dInfo in drv) {    Console.WriteLine(dInfo.Name); }Let us see the complete code −Example Live Demousing System; using System.Linq; using System.IO; public class Demo {    public static void Main() {       var drv = DriveInfo.GetDrives();       foreach (DriveInfo dInfo in drv) {          Console.WriteLine(dInfo.Name);       }    } }Output/etc/resolv.conf /etc/hostname /etc/hosts /run/secrets /home/cg/rootNote: The result will vary on different Operating Systems. The above ... Read More

Use the DriveFormat property to get the drive format in C#.Set the drive for which you want to display the format −DriveInfo dInfo = new DriveInfo("C");Now, use DriveFormat to get the drive format −dInfo.DriveFormatThe drive formats for a windows system can be NTFS or FAT32.Here is the complete code −Exampleusing System; using System.Linq; using System.IO; public class Demo {    public static void Main() {       DriveInfo dInfo = new DriveInfo("C");       Console.WriteLine("Drive Format = "+dInfo.DriveFormat);    } }OutputThe following is the output −Drive Format = NTFS

Use the RootDirectory property to get the name of the root directory.Firstly, use DriveInfo to set the drive for which you want the root directory −DriveInfo dInfo = new DriveInfo("C");Now, the RootDirectory gives you the result −dInfo.RootDirectoryExampleHere is the complete code −using System; using System.Linq; using System.IO; public class Demo {    public static void Main() {       DriveInfo dInfo = new DriveInfo("C");       Console.WriteLine("Root Directory: "+dInfo.RootDirectory);    } }OutputThe following is the output −C:\