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   Flags  public enum Age       New Born   1      Toddler   2      Preschool   4      Kindergarten   8     I could use if statement for right now  but if my Enum list gets bigger  I want to find a better way to do it  I am thinking about to use Linq  just not sure how to do it

User · Answer

I ve got a handy extension method that uses TryParse  as IsDefined is case-sensitive   public static bool IsParsable lt T gt  this string value  where T   struct       return Enum TryParse lt T gt  value  true  out

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To parse the age   Age age  if  Enum TryParse typeof Age    New Born   out age     MessageBox Show  Defined        Defined for  New Born  1  4   8  12    To see if it is defined   if  Enum IsDefined typeof Age    New Born       MessageBox Show  Defined      Depending on how you plan to use the Age enum  flags may not be the right thing   As you probably know   Flags  indicates you want to allow multiple values  as in a bit mask    IsDefined will return false for Age Toddler   Age Preschool because it has multiple values

User · Answer

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 lt T gt  this T value  string metaDataDescription                return GetValueFromMetaDataAttribute value  metaDataDescription  FirstOrDefault               private static IEnumerable lt string gt  GetValueFromMetaDataAttribute lt T gt  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 lt string gt                public static List lt T gt  GetEnumeratesByMetaData lt T gt  string metadataDescription  string value                return             typeof  T  GetEnumValues   Cast lt T gt    Where                  enumerate   gt                      GetValueFromMetaDataAttribute enumerate  metadataDescription  Any                          p   gt  p ToLower      value ToLower     ToList               public static List lt T gt  GetNotEnumeratesByMetaData lt T gt  string metadataDescription  string value                return             typeof  T  GetEnumValues   Cast lt T gt    Where                  enumerate   gt                      GetValueFromMetaDataAttribute enumerate  metadataDescription  All                          p   gt  p ToLower      value ToLower     ToList               you can then do something like  var enumerates   MetadataHelper GetEnumeratesByMetaData lt Age gt   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

User · Answer

You can use    Enum IsDefined typeof Age   youragevariable

User · Answer

You can use the Enum TryParse method   Age age  if  Enum TryParse lt Age gt   New Born   out age            You now have the value in age

User · Answer

You can use the TryParse method that returns true if it successful   Age age   if Enum TryParse lt Age gt   myString   out age          Here you can use age

User · Answer

You should use Enum TryParse to achive your goal  This is a example    Flags  private enum TestEnum       Value1   1      Value2   2    static void Main string   args        var enumName    Value1       TestEnum enumValue       if   TestEnum TryParse enumName  out enumValue                 throw new Exception  Wrong enum value                  enumValue contains parsed value

[c#] how to check if string value is in the Enum list?

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