public static void AnonymousTypeProjection()
{
var employees = new SampleData().GetEmployees();
var empdata = from e in employees
select new { e.EmployeeName, e.Department };
//do some code
}
public static void FirstVsFirstOrDefault()
{
var employees = new SampleData().GetEmployees();
////throws error
//var empdata = employees.Where(e => e.EmployeeId == 200).First();
var empdata1 = employees.Where(e => e.EmployeeId == 200).FirstOrDefault();
if (empdata1 == null)
{
Console.WriteLine("Employee not found");
}
Console.Read();
}
public static void DeferredQueryExecution()
{
var employees = new SampleData().GetEmployees();
float increment = 0;
increment = 1;//wont apply
var empdata = from e in employees
select new { e.EmployeeName, e.Salary, NewSalary = (e.Salary + increment) };
increment = 2000;//this will apply
foreach (var emp in empdata)
{
Console.WriteLine("-------------------------------------------------------------------------");
Console.WriteLine("Employee Name: " + emp.EmployeeName);
Console.WriteLine("Employee Old Salary: " + emp.Salary);
Console.WriteLine("Employee New Salary: " + emp.NewSalary);
}
Console.Read();
}
public static void FunctionsInLinq()
{
var employees = new SampleData().GetEmployees();
var empdata = from e in employees
select new { e.EmployeeId, e.EmployeeName, e.Salary, Tax = CalculateTax(e) };
foreach (var emp in empdata)
{
Console.WriteLine("-------------------------------------------------------------------------");
Console.WriteLine("Employee Name: " + emp.EmployeeName);
Console.WriteLine("Employee Salary: " + emp.Salary);
Console.WriteLine("Employee Tax: " + emp.Tax);
}
Console.Read();
}
public static void BasicEntitySample()
{
var employees = new SampleData().GetEmployees();
var empdata = employees.Where(e => e.Department == "Sales");
}
public static void IndexedQueries()
{
var employees = new SampleData().GetEmployees();
//var selectedEmps = employees.Where(emp => emp.Department == "Sales");
var selectedEmps = employees.Where((emp, index) => ((index != 0) ? true : false));
foreach (var emp in selectedEmps)
{
Console.WriteLine("Employee Name: " + emp.EmployeeName);
}
Console.Read();
}
public static void GroupedEmployees()
{
var employees = new SampleData().GetEmployees();
var departmentsAndItsEmps = from e in employees
group e by e.Department into groupedData
select new { Department = groupedData.Key, Employees = groupedData };
foreach (var oneDeptAndItsEmployees in departmentsAndItsEmps)
{
Console.WriteLine("-------------------------------------------------------------------------");
Console.WriteLine("Department: " + oneDeptAndItsEmployees.Department);
foreach (var empsInDept in oneDeptAndItsEmployees.Employees)
{
Console.WriteLine("Employee Name: " + empsInDept.EmployeeName);
}
}
Console.Read();
}