Basic Of LINQ

using System;
using System.Linq;
namespace LINQtoSQL {
    class LinqToSQLCRUD {
        static void Main(string[] args) {
            string connectString = System.Configuration.ConfigurationManager.ConnectionStrings["LinqToSQLDBConnectionString"].ToString();
            LinqToSQLDataContext db = new LinqToSQLDataContext(connectString);
            //Create new Employee
            Employee newEmployee = new Employee();
            newEmployee.Name = "ABC";
            newEmployee.Email = "[email protected]";
            newEmployee.ContactNo = "1234567890";
            newEmployee.DepartmentId = 3;
            newEmployee.Address = "India";
            //Add new Employee to database
            db.Employees.InsertOnSubmit(newEmployee);
            //Save changes to Database.
            db.SubmitChanges();
            //Get new Inserted Employee
            Employee insertedEmployee = db.Employees.FirstOrDefault(e => e.Name.Equals("Michael"));
            Console.WriteLine("Employee Id = {0} , Name = {1}, Email = {2}, ContactNo = {3}, Address = {4}", insertedEmployee.EmployeeId, insertedEmployee.Name, insertedEmployee.Email, insertedEmployee.ContactNo, insertedEmployee.Address);
            Console.WriteLine("\nPress any key to continue.");
            Console.ReadKey();
        }
    }
}
using System;
using System.Linq;
namespace LINQtoSQL {
    class LinqToSQLCRUD {
        static void Main(string[] args) {
            string connectString = System.Configuration.ConfigurationManager.ConnectionStrings["LinqToSQLDBConnectionString"].ToString();
            LinqToSQLDataContext db = new LinqToSQLDataContext(connectString);
            //Get Employee for update
            Employee employee = db.Employees.FirstOrDefault(e => e.Name.Equals("Michael"));
            newEmployee.Name = "ABC";
            newEmployee.Email = "[email protected]";
            newEmployee.ContactNo = "9954567890";
            newEmployee.DepartmentId = 3;
            newEmployee.Address = "India-Delhi";
            //Save changes to Database.
            db.SubmitChanges();
            //Get Updated Employee
            Employee updatedEmployee = db.Employees.FirstOrDefault(e => e.Name.Equals("George Michael"));
            Console.WriteLine("Employee Id = {0} , Name = {1}, Email = {2}, ContactNo = {3}, Address = {4}", updatedEmployee.EmployeeId, updatedEmployee.Name, updatedEmployee.Email, updatedEmployee.ContactNo, updatedEmployee.Address);
            Console.WriteLine("\nPress any key to continue.");
            Console.ReadKey();
        }
    }
}
using System;
using System.Linq;
namespace LINQtoSQL {
    class LinqToSQLCRUD {
        static void Main(string[] args) {
            string connectString = System.Configuration.ConfigurationManager.ConnectionStrings["LinqToSQLDBConnectionString"].ToString();
            LinqToSQLDataContext db = newLinqToSQLDataContext(connectString);
            //Get Employee to Delete
            Employee deleteEmployee = db.Employees.FirstOrDefault(e => e.Name.Equals("ABC"));
            //Delete Employee
            db.Employees.DeleteOnSubmit(deleteEmployee);
            //Save changes to Database.
            db.SubmitChanges();
            //Get All Employee from Database
            var employeeList = db.Employees;
            foreach(Employee employee in employeeList) {
                Console.WriteLine("Employee Id = {0} , Name = {1}, Email = {2}, ContactNo = {3}", employee.EmployeeId, employee.Name, employee.Email, employee.ContactNo);
            }
            Console.WriteLine("\nPress any key to continue.");
            Console.ReadKey();
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace LINQtoObjects {
    class Program {
        static void Main(string[] args) {
            string[] tools = {
                "A",
                "B",
                "C",
                "D",
                "E",
                "F"
            };
            var list = from t in tools
            select t;
            StringBuilder sb = new StringBuilder();
            foreach(string s in list) {
                sb.Append(s + Environment.NewLine);
            }
            Console.WriteLine(sb.ToString(), "Tools");
            Console.ReadLine();
        }
    }
}