Enum localization

Quoter picture Quoter · Jun 29, 2013 · Viewed 58.9k times · Source

How do you localize enums for a ListBoxFor where multiple options are possible?

For example an enum that contains roles:

public enum RoleType
{
    [Display(Description = "Administrator", ResourceType = typeof(Resource))]
    Administrator = 1,
    [Display(Description = "Moderator", ResourceType = typeof(Resource))]
    Moderator = 2,
    [Display(Description = "Webmaster", ResourceType = typeof(Resource))]
    Webmaster = 3,
    [Display(Description = "Guest", ResourceType = typeof(Resource))]
    Guest = 4,
    Etc.... = 5,
}

I have seen this done with dropdownlist/selectlists. But is there a way to do this for a multi select list?

[EDIT]

This is how I'd like to use it, which is how it works now but doesn't get translated in a different language:

var roles = from role r in Enum.GetValues(typeof(RoleType))
            select new
            {
               Id = (int)Enum.Parse(typeof(RoleType), r.ToString()),
               Name = r.ToString()
            };

searchModel.roles = new MultiSelectList(roles, "Id", "Name");

Note: i have renamed the enum from Role to RoleType.

Answer

eluxen picture eluxen · Jun 29, 2013

You can implement a description attribute.

public class LocalizedDescriptionAttribute : DescriptionAttribute
{
     private readonly string _resourceKey;
    private readonly ResourceManager _resource;
    public LocalizedDescriptionAttribute(string resourceKey, Type resourceType)
    {
        _resource = new ResourceManager(resourceType);
        _resourceKey = resourceKey;
    }

    public override string Description
    {
        get
        {
            string displayName = _resource.GetString(_resourceKey);

            return string.IsNullOrEmpty(displayName)
                ? string.Format("[[{0}]]", _resourceKey)
                : displayName;
        }
    }
}

public static class EnumExtensions
{
    public static string GetDescription(this Enum enumValue) 
    {
        FieldInfo fi = enumValue.GetType().GetField(enumValue.ToString());

        DescriptionAttribute[] attributes =
            (DescriptionAttribute[])fi.GetCustomAttributes(
            typeof(DescriptionAttribute),
            false);

        if (attributes != null &&
            attributes.Length > 0)
            return attributes[0].Description;
        else
            return enumValue.ToString();
    }
}

Define it like this:

public enum Roles
{
    [LocalizedDescription("Administrator", typeof(Resource))]
    Administrator,
...
}

And use it like this:

var roles = from RoleType role in Enum.GetValues(typeof(RoleType))
                    select new
                    {
                        Id = (int)role,
                        Name = role.GetDescription()
                    };
 searchModel.roles = new MultiSelectList(roles, "Id", "Name");