Let’s say we want to remove whitespace from the following string str1.string str1 = "Brad Pitt";Now, use Regex Replace to replace whitespace with empty. Here, we have used System.Text.RegularExpressions.string str2 = System.Text.RegularExpressions.Regex.Replace(str1, @"\s+", "");Let us see the complete example.Example Live Demousing System; using System.Text.RegularExpressions; namespace Demo {    class Program {       static void Main(string[] args) {          string str1 = "Brad Pitt";          Console.WriteLine(str1);          string str2 = System.Text.RegularExpressions.Regex.Replace(str1, @"\s+", "");          Console.WriteLine(str2);       }    } }OutputBrad Pitt BradPitt

The method returns a single specific element of a sequence. If the element is not present in the sequence, then the default value is returned.We have two string arrays here.string[] str1 = { "one" }; string[] str2 = { };First array is checked for a single element, whereas the second array is empty and checked using SingleorDefault.str2.AsQueryable().SingleOrDefault();The following is an example showing the usage of SingleorDefault() method.Example Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       string[] str1 = { "one" };       string[] str2 = { }; ... Read More

The Single() method returns the only element that satisfies a condition. If more than one such element is visible, then an error is thrown.The following is our string array.string[] str = { "jack", "tom", "henry", "time"};Now, use the Single() method to get each element. Then, we have used Lambda Expression to calculate an element whose length is greater than four.str.AsQueryable().Single(name => name.Length > 4);Example Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       string[] str = { "jack", "tom", "henry", "time"};       // finding string whose length is ... Read More

Get only a single element of a sequence using the Single() method.Let’s say we have a string array with only one element.string[] str = { "one" };Now, get the element.str.AsQueryable().Single();Here is our code.Example Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       string[] str = { "one" };       string res = str.AsQueryable().Single();       Console.WriteLine(res);    } }Outputone

Use ReadAllLines() method to read all the lines one by one in a file.Let’s say we have a file “new.txt” with the following lines.One Two ThreeFirstly, set the path of the file to be read.String myPath = "new.txt";Now add it under a string array to fetch the lines on by one.String[] fLine = File.ReadAllLines(myPath);Let’s say you need to fetch the first line. For that.fLine[0]The following is the complete example that reads lines one by one in a file.Exampleusing System; using System.IO; public class Demo {    public static void Main() {       String myPath = "new.txt";     ... Read More

Declare a string array.string [] students = {"Jenifer", "Angelina", "Vera"};Add it to a LinkedList.string [] students = {"Jenifer", "Angelina", "Vera"};Now, use AddLast() method to add a node at the end.list.AddLast("Anne");Example Live Demousing System; using System.Collections.Generic; class Demo {    static void Main() {       string [] students = {"Jenifer", "Angelina", "Vera"};       LinkedList list = new LinkedList(students);       foreach (var stu in list) {          Console.WriteLine(stu);       }       // add a node at the end       Console.WriteLine("Node added at the last...");       list.AddLast("Anne"); ... Read More

To check whether two sequences are equal or not, use the SequenceEqual() method.Firstly, set the sequences.Employee emp1 = new Employee { EmployeeRank = 4, EmpName = "Amit", EmpMarks = 90 }; Employee emp2 = new Employee { EmployeeRank = 5, EmpName = "Raman", EmpMarks = 95 }; List employee1 = new List { emp1, emp2 }; List employee2 = new List { emp1, emp2 };Now, find whether the sequences are equal or not.employee1.AsQueryable().SequenceEqual(employee2);Here is the example that shows the result.Exmaple Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       Employee ... Read More

Use SelectMany method to collapse elements into a single collection like an error.An example would be to convert string to character array. The following is our string array.string[] str = { "Mobile", "Laptop", "Tablet" };Now, convert to character array.str.SelectMany(item => item.ToCharArray());Example Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       string[] str = { "Mobile", "Laptop", "Tablet" };       var res = str.SelectMany(item => item.ToCharArray());       Console.WriteLine("String converted to character array: ");       foreach (char letter in res) {          Console.Write(letter);       }    } }OutputString converted to character array: MobileLaptopTablet

Use the Select method to modify the elements in an array.The following is our string array.string[] stationery = { "diary", "board", "pencil", "whiteboard" };The Select method also specifies Lambda Expressions as shown below −Example Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       string[] stationery = { "diary", "board", "pencil", "whiteboard" };       var res = stationery.AsQueryable().Select((item, index) => new { result = item.Substring(0, index + 4) });       foreach (var str in res) {          Console.WriteLine("{0}", str);       }    } }Output{ result = diar } { result = board } { result = pencil } { result = whitebo }

Use Select method and Lambda Expression to calculate the cube of elements.The following is our list.List list = new List { 2, 4, 5, 7 };Now, use the Select() method and calculate the cube.list.AsQueryable().Select(c => c * c * c);The following is the entire example.Example Live Demousing System; using System.Linq; using System.Collections.Generic; public class Demo {    public static void Main() {       List list = new List { 2, 4, 5, 7 };       Console.WriteLine("Elements...");       // initial list javascript:void(0)       foreach (int n in list)       Console.WriteLine(n);     ... Read More