what is the use of into and let in LINQ. please help

Question

Sumit Joshi · Answer

Hi siddarth Into : The Into keyword allows creating a temporary variable to store the results of a group join or select clause into a new variable. var em = from e in emp group e by new{ e.DeptId} into gEmp where gEmp.Count() > 1 select new { gEmp.Key.DeptId salary = gEmp.Sum(t => t.Salary) }; In the above query after applying into on grouping it creates a IGrouping type gEmp variable which is used to apply the next filter. Note : Into is used when you want to perform an operation on grouped data. Let : The Let keyword allows storing the results of a query which can be used in a subsequent query; i.e. it creates a new variable and initializes it with the result of the expression you supply. var em = from e in emp group e by new { e.Salary e.Id } into gEmp let avgsal = (gEmp.Sum(t => t.Salary) / gEmp.Count()) where gEmp.Key.Salary == avgsal select new { gEmp.Key.Salary gEmp.Key.Id }; If found helpful Mark as Correct Answer

Sumit Joshi · Answer

Thanks.

Anil Kumar · Answer

Check this Article.. http://www.codeproject.com/Articles/231164/Into-and-let-in-LINQ-Let-vs-Into

pritaeas · Answer

Here is a nice article on the subject.