In SQL Server, we are very familiar with IN keyword and we use this keyword in many times which is very helpful for us. It save our extra efforts and code line like below query.

To achieve this in LINQ , we heve below two mechanism.

• Using Contain function
• Using JOIN

1.)  Contain keyword on Array

Lets take an array EmployesID where we store our employee ID and check column emp.ID IN EmployesID array as below :

var EmployesID = new[] { 1,2,3,4,5 };

         (from emp in dbContext.Employes
          join EmpAdd in dbContext.EmpAddress on emp.Id equals EmpAdd.EmployeeId
          where EmployesID.Contains(emp.ID)
          select emp.Name);

2.) JOIN on Array

Here we join our array with ID as below :

var EmployesID = new[] { 1,2,3,4,5 };

           (from emp in dbContext.Employes
           join abc in EmployesID on emp.ID equals abc
           select emp.Name);

Apply Contain keyword on collection can make impact on performance so here we recommend to use JOIN on array.