user.EmployeeID = Convert.ToInt32(loginControl.UserName);
brother make sure that
Employee has the prpoerty
EmployeeID type of string?
command.Parameters.AddWithValue("@EmployeeID", employee.EmployeeID);
explain here first that what is data type of
EmployeeID in your database?
also, what is the data type of
EmployeeID in your object? then some one would guess, what's going on exactly