Question

I need a count for the GetUsers but I have 3 different calculations either by alpha, search and byEmail parameters what can I do in this situation for my ObjectDataSource SelectCount method

public class Users
{
    public IList<MembershipUser> GetUsers(string alpha, string search, bool byEmail, int startRowIndex, int maximumRows)
    {
        IList<MembershipUser> users = null;

        if (alpha != null && search == null)
        {
            users = Membership.GetAllUsers().Cast<MembershipUser>().Where(x => x.UserName.StartsWith(alpha) == true).ToList();
        }
        else if (search != null && !byEmail)
        {
            users = Membership.FindUsersByName(search).Cast<MembershipUser>().Skip(maximumRows * startRowIndex).Take(maximumRows).ToList();
        }
        else
        {
            users = Membership.FindUsersByEmail(search).Cast<MembershipUser>().Skip(maximumRows * startRowIndex).Take(maximumRows).ToList();
        }

        return users;

    }

    public int GetUserCount()
    {

    }

Updated C#:

    public IEnumerable<MembershipUser> GetUsers(string alpha, string searchBy, string searchText, int startRowIndex, int maximumRows)
    {
        var users = Membership.GetAllUsers().Cast<MembershipUser>();

        if (alpha != null && string.IsNullOrEmpty(searchBy))
        {
            users = users
                .Where(x => x.UserName.StartsWith(alpha, StringComparison.OrdinalIgnoreCase))
                .Skip(maximumRows * startRowIndex)
                .Take(maximumRows).ToList();
        }
        else if (searchBy == "User Name" && !string.IsNullOrEmpty(searchText))
        {
            users = users.Where(x => x.UserName == searchText)
                .Skip(maximumRows * startRowIndex)
                .Take(maximumRows).ToList();
        }
        else if (searchBy == "Email" && !string.IsNullOrEmpty(searchText))
        {
            users = users.Where(x => x.Email == searchText)
                .Skip(maximumRows * startRowIndex)
                .Take(maximumRows).ToList();
        }
        else
        {
            users = null;
        }

        return users;

    }

Answer 1

Something like the following should work:

public int GetUserCount(string alpha, string search, bool byEmail, int startRowIndex, int maximumRows)
{
    var users = Membership.GetAllUsers().Cast<MembershipUser>();

    if (alpha != null && search == null)
    {
        users = users.Where(x => x.UserName.StartsWith(alpha) == true);
    }
    else if (search != null && !byEmail)
    {
        users = users.FindUsersByName(search).Cast<MembershipUser>();
    }
    else
    {
        users = users.FindUsersByEmail(search);
    }

    return users.Count();
}

I would be more comfortable with this approach if FindUsersByName and FindUsersByEmail returned objects related to IEnumerable<T> so you could depend on the lazy nature of LINQ, but in this case it doesn’t matter since you’re doing a count. I’d recommend some form of Select to limit the fields being queried over, but in your second two cases, they’ll pull all results anyway so it would be without benefit 2/3 possible situations. If you find that more often than not the query is done by UserName then it would probably be worth adding there.