假设GPUShaderAttribute：
[AttributeUsage(AttributeTargets.Field,AllowMultiple =false)]
public class GPUShaderAttribute: Attribute
{
public GPUShaderAttribute(string value)
{
Value = value;
}
public string Value { get; internal set; }
}
然后我们可以编写一些通用方法来返回枚举值和GPUShaderAttribute 对象的字典。
/// <summary>
/// returns the attribute for a given enum
/// </summary>
public static TAttribute GetAttribute<TAttribute>(IConvertible @enum)
{
TAttribute attributeValue = default(TAttribute);
if (@enum != null)
{
FieldInfo fi = @enum.GetType().GetField(@enum.ToString());
attributeValue = fi == null ? attributeValue : (TAttribute)fi.GetCustomAttributes(typeof(TAttribute), false).DefaultIfEmpty(null).FirstOrDefault();
}
return attributeValue;
}
然后用这个方法返回整个集合。
/// <summary>
/// Returns a dictionary of all the Enum fields with the attribute.
/// </summary>
public static Dictionary<Enum, RAttribute> GetEnumObjReference<TEnum, RAttribute>()
{
Dictionary<Enum, RAttribute> _dict = new Dictionary<Enum, RAttribute>();
Type enumType = typeof(TEnum);
Type enumUnderlyingType = Enum.GetUnderlyingType(enumType);
Array enumValues = Enum.GetValues(enumType);
foreach (Enum enumValue in enumValues)
{
_dict.Add(enumValue, GetAttribute<RAttribute>(enumValue));
}
return _dict;
}
如果你只是想要一个字符串值，我会推荐一个稍微不同的路线。
/// <summary>
/// Returns the string value of the custom attribute property requested.
/// </summary>
public static string GetAttributeValue<TAttribute>(IConvertible @enum, string propertyName = "Value")
{
TAttribute attribute = GetAttribute<TAttribute>(@enum);
return attribute == null ? null : attribute.GetType().GetProperty(propertyName).GetValue(attribute).ToString();
}
/// <summary>
/// Returns a dictionary of all the Enum fields with the string of the property from the custom attribute nulls default to the enumName
/// </summary>
public static Dictionary<Enum, string> GetEnumStringReference<TEnum, RAttribute>(string propertyName = "Value")
{
Dictionary<Enum, string> _dict = new Dictionary<Enum, string>();
Type enumType = typeof(TEnum);
Type enumUnderlyingType = Enum.GetUnderlyingType(enumType);
Array enumValues = Enum.GetValues(enumType);
foreach (Enum enumValue in enumValues)
{
string enumName = Enum.GetName(typeof(TEnum), enumValue);
string decoratorValue = Common.GetAttributeValue<RAttribute>(enumValue, propertyName) ?? enumName;
_dict.Add(enumValue, decoratorValue);
}
return _dict;
}