/* EXAMPLE OF Implementation.
[Flags]
public enum DaysOfTheWeek : short
{
[StringValue("Sunday")]
Sunday = 1,
[StringValue("Monday")]
Monday = 2,
[StringValue("Tuesday")]
Tuesday = 4,
[StringValue("Wednesday")]
Wednesday = 8,
[StringValue("Thursday")]
Thursday = 16,
[StringValue("Friday")]
Friday = 32,
[StringValue("Saturday")]
Saturday = 64,
[StringValue("AllDays")]
AllDays = Saturday | Friday | Thursday | Wednesday | Tuesday | Monday | Sunday,
}
*/
#region Class StringEnum
///
/// Helper class for working with 'extended' enums using attributes.
///
public class StringEnum
{
#region Instance implementation
private static readonly Hashtable StringValues = new Hashtable();
private readonly Type _enumType;
///
/// Creates a new instance.
///
/// Enum type.
public StringEnum(Type enumType)
{
if (!enumType.IsEnum)
throw new ArgumentException(String.Format("Supplied type must be an Enum. Type was {0}", enumType));
_enumType = enumType;
}
///
/// Gets the underlying enum type for this instance.
///
///
public Type EnumType
{
get { return _enumType; }
}
///
/// Gets the string value associated with the given enum value.
///
/// Name of the enum value.
/// String Value
public string GetStringValue(string valueName)
{
string stringValue = null;
try
{
var enumType = (Enum) Enum.Parse(_enumType, valueName);
stringValue = GetStringValue(enumType);
}
catch
{
//Swallow!
}
return stringValue;
}
///
/// Gets the string values associated with the enum.
///
/// String value array
public Array GetStringValues()
{
var values = new ArrayList();
//Look for our string value associated with fields in this enum
foreach (FieldInfo fi in _enumType.GetFields())
{
//Check for our custom attribute
var attrs = fi.GetCustomAttributes(typeof (StringValueAttribute), false) as StringValueAttribute[];
if (attrs != null)
if (attrs.Length > 0)
values.Add(attrs[0].Value);
}
return values.ToArray();
}
///
/// Gets the values as a 'bindable' list datasource.
///
/// IList for data binding
public IList GetListValues()
{
Type underlyingType = Enum.GetUnderlyingType(_enumType);
var values = new ArrayList();
//Look for our string value associated with fields in this enum
foreach (FieldInfo fi in _enumType.GetFields())
{
//Check for our custom attribute
var attrs = fi.GetCustomAttributes(typeof (StringValueAttribute), false) as StringValueAttribute[];
if (attrs != null)
if (attrs.Length > 0)
values.Add(new DictionaryEntry(Convert.ChangeType(Enum.Parse(_enumType, fi.Name), underlyingType),
attrs[0].Value));
}
return values;
}
///
/// Return the existence of the given string value within the enum.
///
/// String value.
/// Existence of the string value
public bool IsStringDefined(string stringValue)
{
return Parse(_enumType, stringValue) != null;
}
///
/// Return the existence of the given string value within the enum.
///
/// String value.
/// Denotes whether to conduct a case-insensitive match on the supplied string value
/// Existence of the string value
public bool IsStringDefined(string stringValue, bool ignoreCase)
{
return Parse(_enumType, stringValue, ignoreCase) != null;
}
#endregion
#region Static implementation
///
/// Gets a string value for a particular enum value.
///
/// Value.
/// String Value associated via a attribute, or null if not found.
public static string GetStringValue(Enum value)
{
string output = null;
Type type = value.GetType();
if (StringValues.ContainsKey(value))
output = ((StringValueAttribute) StringValues[value]).Value;
else
{
//Look for our 'StringValueAttribute' in the field's custom attributes
FieldInfo fi = type.GetField(value.ToString());
var attrs = fi.GetCustomAttributes(typeof (StringValueAttribute), false) as StringValueAttribute[];
if (attrs != null)
if (attrs.Length > 0)
{
StringValues.Add(value, attrs[0]);
output = attrs[0].Value;
}
}
return output;
}
///
/// Parses the supplied enum and string value to find an associated enum value (case sensitive).
///
/// Type.
/// String value.
/// Enum value associated with the string value, or null if not found.
public static object Parse(Type type, string stringValue)
{
return Parse(type, stringValue, false);
}
///
/// Parses the supplied enum and string value to find an associated enum value.
///
/// Type.
/// String value.
/// Denotes whether to conduct a case-insensitive match on the supplied string value
/// Enum value associated with the string value, or null if not found.
public static object Parse(Type type, string stringValue, bool ignoreCase)
{
object output = null;
string enumStringValue = null;
if (!type.IsEnum)
throw new ArgumentException(String.Format("Supplied type must be an Enum. Type was {0}", type));
//Look for our string value associated with fields in this enum
foreach (FieldInfo fi in type.GetFields())
{
//Check for our custom attribute
var attrs = fi.GetCustomAttributes(typeof (StringValueAttribute), false) as StringValueAttribute[];
if (attrs != null)
if (attrs.Length > 0)
enumStringValue = attrs[0].Value;
//Check for equality then select actual enum value.
if (string.Compare(enumStringValue, stringValue, ignoreCase) == 0)
{
output = Enum.Parse(type, fi.Name);
break;
}
}
return output;
}
///
/// Return the existence of the given string value within the enum.
///
/// String value.
/// Type of enum
/// Existence of the string value
public static bool IsStringDefined(Type enumType, string stringValue)
{
return Parse(enumType, stringValue) != null;
}
///
/// Return the existence of the given string value within the enum.
///
/// String value.
/// Type of enum
/// Denotes whether to conduct a case-insensitive match on the supplied string value
/// Existence of the string value
public static bool IsStringDefined(Type enumType, string stringValue, bool ignoreCase)
{
return Parse(enumType, stringValue, ignoreCase) != null;
}
#endregion
}
#endregion
#region Class StringValueAttribute
///
/// Simple attribute class for storing String Values
///
public class StringValueAttribute : Attribute
{
private readonly string _value;
///
/// Creates a new instance.
///
/// Value.
public StringValueAttribute(string value)
{
_value = value;
}
///
/// Gets the value.
///
///
public string Value
{
get { return _value; }
}
}
#endregion
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