how to use enum with DescriptionAttribute in asp.net mvc

Question

I am new to asp.net MVC. I am trying to use dropdown control on my view page, which populates from enum. I also want to add custom descriptions to dropdown values. I searched so

Answer 1

I created a helper class that tries different types of attributes. I needed it because I was using bootstrap with https://github.com/civicsource/enums and https://silviomoreto.github.io/bootstrap-select/

public static class EnumHelper
    {
        static EnumHelper()
        {
            var enumType = typeof(T);
            if (!enumType.IsEnum) { throw new ArgumentException("Type '" + enumType.Name + "' is not an enum"); }
        }

        public static string GetEnumDescription(T value)
        {
            var fi = typeof(T).GetField(value.ToString());
            var attributes = (DescriptionAttribute[]) fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
            return attributes.Length > 0 ? attributes[0].Description : value.ToString();
        }

        public static IEnumerable GetSelectList()
        {
            var groupDictionary = new Dictionary();

            var enumType = typeof(T);
            var fields = from field in enumType.GetFields()
                         where field.IsLiteral
                         select field;

            foreach (var field in fields)
            {
                var display = field.GetCustomAttribute(false);
                var description = field.GetCustomAttribute(false);
                var group = field.GetCustomAttribute(false);

                var text = display?.GetName() ?? display?.GetShortName() ?? display?.GetDescription() ?? display?.GetPrompt() ?? description?.Description ?? field.Name;
                var value = field.Name;
                var groupName = display?.GetGroupName() ?? group?.Category ?? string.Empty;
                if (!groupDictionary.ContainsKey(groupName)) { groupDictionary.Add(groupName, new SelectListGroup { Name = groupName }); }

                yield return new SelectListItem
                {
                    Text = text,
                    Value = value,
                    Group = groupDictionary[groupName],
                };
            }
        }
    }

And you call it like:

   @Html.LabelFor(model => model.Address.State, htmlAttributes: new { @class = "control-label col-md-2" })
   

      @Html.DropDownListFor(model => model.Address.State, EnumHelper.GetSelectList(), new { @class = "selectpicker show-menu-arrow", data_live_search = "true" })
      @Html.ValidationMessageFor(model => model.Address.State, "", new { @class = "text-danger" })
   

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