how to check if string value is in the Enum list?

Question

In my query string, I have an age variable ?age=New_Born.

Is there a way I can check if this string value New_Born is in my Enum list

Answer 1

I know this is an old thread, but here's a slightly different approach using attributes on the Enumerates and then a helper class to find the enumerate that matches.

This way you could have multiple mappings on a single enumerate.

public enum Age
{
    [Metadata("Value", "New_Born")]
    [Metadata("Value", "NewBorn")]
    New_Born = 1,
    [Metadata("Value", "Toddler")]
    Toddler = 2,
    [Metadata("Value", "Preschool")]
    Preschool = 4,
    [Metadata("Value", "Kindergarten")]
    Kindergarten = 8
}

With my helper class like this

public static class MetadataHelper
{
    public static string GetFirstValueFromMetaDataAttribute(this T value, string metaDataDescription)
    {
        return GetValueFromMetaDataAttribute(value, metaDataDescription).FirstOrDefault();
    }

    private static IEnumerable GetValueFromMetaDataAttribute(T value, string metaDataDescription)
    {
        var attribs =
            value.GetType().GetField(value.ToString()).GetCustomAttributes(typeof (MetadataAttribute), true);
        return attribs.Any()
            ? (from p in (MetadataAttribute[]) attribs
                where p.Description.ToLower() == metaDataDescription.ToLower()
                select p.MetaData).ToList()
            : new List();
    }

    public static List GetEnumeratesByMetaData(string metadataDescription, string value)
    {
        return
            typeof (T).GetEnumValues().Cast().Where(
                enumerate =>
                    GetValueFromMetaDataAttribute(enumerate, metadataDescription).Any(
                        p => p.ToLower() == value.ToLower())).ToList();
    }

    public static List GetNotEnumeratesByMetaData(string metadataDescription, string value)
    {
        return
            typeof (T).GetEnumValues().Cast().Where(
                enumerate =>
                    GetValueFromMetaDataAttribute(enumerate, metadataDescription).All(
                        p => p.ToLower() != value.ToLower())).ToList();
    }

}

you can then do something like

var enumerates = MetadataHelper.GetEnumeratesByMetaData("Value", "New_Born");

And for completeness here is the attribute:

 [AttributeUsage(AttributeTargets.Field, Inherited = false, AllowMultiple = true)]
public class MetadataAttribute : Attribute
{
    public MetadataAttribute(string description, string metaData = "")
    {
        Description = description;
        MetaData = metaData;
    }

    public string Description { get; set; }
    public string MetaData { get; set; }
}