Design level problem: multiple enums or looping the enum in UI code in order to make visibility decision ?

Question

Hi!, we have a debate about a BEST PRACTISE from a .NET architecture DESIGN POINT OF VIEW:

Task: How to manage role based visibility in UI with enum?

For example: I want to show all team types [a,b,c,d,e] to administrator but only team types [a,b,c] to normal user.

First I have enum which includes all team types:

public enum TeamType { a, b, c, d, e }

I use it like this:

if (IsAdminitrator()) 
    comboboxTeamtypes.Items.AddRange(Enum.GetNames(typeof(TeamType)));

Now I should decide how to implement else clause. Because enums can't be inherited I have two alternative approaches:

1) Should I introduce an other role specific enum:

public enum TeamTypeOthers {a, b, c }

and then I would have:

else
    comboboxTeamtypes.Items.AddRange(Enum.GetNames(typeof(TeamTypeOthers)));

2) Or should I forget creating any role specific enum TeamTypeOthers and just loop the original TeamType enum values in UI-code:

else
{
    foreach (TeamType teamtype in Enum.GetValues(typeof(TeamType)))
    {
        if (asdf == TeamType.a)
            comboboxTeamtypes.Items.Add(teamtype);
        else if (asdf == TeamType.b)
            comboboxTeamtypes.Items.Add(teamtype);
        if (asdf == TeamType.c)
            comboboxTeamtypes.Items.Add(teamtype);
    }
}

I think the first solution is nice and clean (though repetitive which is not so nice). But now I also make decision about the use of enum in deeper architecture than in solution 2 which is probably bad and supports the use of solution 2. To me solution 2 is ugly and messy because I don't like loop cultivation around the code.

Answer 1

What is your programming language? In Java, I would tell you to create enum class like below, but obviously this isn't Java.

public enum TeamType {
    A(false), B(false), C(false), D(true), E(true);
    private final boolean isAdmin;
    public TeamType(boolean isAdmin) {
        this.isAdmin = isAdmin;
    }
    public boolean isAdmin() {
        return this.isAdmin;
    }
}

Answer 2

I would change things a little and use simple bitmasking for permissions:

public enum TeamType
{
    a = 1, // or 00001
    b = 2, // or 00010
    c = 4, // or 00100
    d = 8, // or 01000
    e = 16 // or 10000
}

Then each usertype gets its permission level set (each available permission added together):

int administratorLevel = 32; // 11111
int userLevel = 7; // 00111

And then the bitmasking comes in when you populate your dropdown in the UI:

comboboxTeamTypes.Items.AddRange(
    Enum.GetValues(typeof(TeamType))
        .Where(v => myLevel & v == v)
        .Select(v => Enum.GetName(typeof(TeamType), v));