/// <summary>GetString（式木版）</summary>
/// <typeparam name="T">struct(Enum Field)</typeparam>
/// <param name="value">値</param>
/// <returns>列挙型を文字列化</returns>
public static string ToStringByExpressionTree <T>(this T value) where T : struct
{
// Enum Field
Type type = typeof(T);
if (type.IsEnum == false)
{
throw new ArgumentException("value must be a enum type");
}
else
{
MulticastDelegate multicastDelegate = null;
// MulticastDelegateのロード
if (!EnumToStringByExpressionTreeExtensions.ToStringMethods.TryGetValue(type, out multicastDelegate))
{
// こちらは、FlagsAttributeを処理可能。
multicastDelegate = EnumToStringByExpressionTreeExtensions.CreateToString <T>();
// MulticastDelegateをキャッシュ
EnumToStringByExpressionTreeExtensions.ToStringMethods[type] = multicastDelegate;
}
// MulticastDelegateでFastReflection
Func <T, string> f = (Func <T, string>)multicastDelegate;
return(f(value));
}
}
/// <summary>ToStringByExpressionTree（式木版）</summary>
/// <typeparam name="T">struct(Enum Field)</typeparam>
/// <param name="value">値</param>
/// <returns>列挙型を文字列化</returns>
public static string ToStringByExpressionTree <T>(this Nullable <T> value) where T : struct
{
if (value.HasValue == true)
{
return(EnumToStringByExpressionTreeExtensions.ToStringByExpressionTree(value.Value));
}
else
{
return("");
}
}