Question

    using (var attendanceContext = new AttendanceAppContext())
    {
        var compareLogin = attendanceContext.Attendances.FirstOrDefault(u =>
        u.LoginDate == DateTime.Now.Date &&
        u.Employee.Username == user.Username);

The code is continued and the compareLogin variable is used later but here an exception is thrown that says:
“The specified type member ‘Date’ is not supported in LINQ to Entities. Only initializer, entity members, and entity navigation properties are supported.

Please help and tell me how I should compare the dates from the database.

Answer 1

You may use TruncateTime function:

using (var attendanceContext = new AttendanceAppContext())
{
    var compareLogin = attendanceContext.Attendances.FirstOrDefault(u =>
    EntityFunctions.TruncateTime(u.LoginDate) == EntityFunctions.TruncateTime(DateTime.Now) &&
    u.Employee.Username == user.Username);
}

Also if u.LoginDate is date without time in your database you may try to use DateTime.Today instead of DateTime.Now.Date. If it doesn’t work just extract it into some variable (e.g var today = DateTime.Today) and use it in your LINQ expression.