C#自定義Attribute值的獲取是開發中會經常用到的，一般我們的做法也就是用反射進行獲取的，程式碼也不是很複雜。

1、首先有如下自定義的Attribute

[AttributeUsage(AttributeTargets.All)]
    public sealed class NameAttribute : Attribute
    {
        private readonly string _name;

        public string Name
        {
            get { return _name; }
        }

        public NameAttribute(string name)
        {
            _name = name;
        }
    }
 

[Name("dept")]
    public class CustomAttributes
    {
        [Name("Deptment Name")]
        public string Name { get; set; }
        [Name("Deptment Address")]
        public string Address;
    }

private static string GetName()
        {
            var type = typeof(CustomAttributes);
            var attribute = type.GetCustomAttributes(typeof(NameAttribute), false).FirstOrDefault();
            if (attribute == null)
            {
                return null;
            }
            return ((NameAttribute)attribute).Name;
        }
 

private static string GetAddress()
        {
            var type = typeof (CustomAttributes);
            var fieldInfo = type.GetField("Address");
            if (fieldInfo == null)
            {
                return null;
            }
            var attribute = fieldInfo.GetCustomAttributes(typeof(NameAttribute), false).FirstOrDefault();
            if (attribute == null)
            {
                return null;
            }
            return ((NameAttribute) attribute).Name;
        }
 

public static class CustomAttributeHelper
    { 
        /// <summary>
        /// Cache Data
        /// </summary>
        private static readonly Dictionary<string, string> Cache = new Dictionary<string, string>();

        /// <summary>
        /// 獲取CustomAttribute Value
        /// </summary>
        /// <typeparam name="T">Attribute的子型別</typeparam>
        /// <param name="sourceType">頭部標有CustomAttribute類的型別</param>
        /// <param name="attributeValueAction">取Attribute具體哪個屬性值的匿名函式</param>
        /// <returns>返回Attribute的值，沒有則返回null</returns>
        public static string GetCustomAttributeValue<T>(this Type sourceType, Func<T, string> attributeValueAction) where T : Attribute
        {
            return GetAttributeValue(sourceType, attributeValueAction, null);
        }

        /// <summary>
        /// 獲取CustomAttribute Value
        /// </summary>
        /// <typeparam name="T">Attribute的子型別</typeparam>
        /// <param name="sourceType">頭部標有CustomAttribute類的型別</param>
        /// <param name="attributeValueAction">取Attribute具體哪個屬性值的匿名函式</param>
        /// <param name="name">field name或property name</param>
        /// <returns>返回Attribute的值，沒有則返回null</returns>
        public static string GetCustomAttributeValue<T>(this Type sourceType, Func<T, string> attributeValueAction,
            string name) where T : Attribute
        {
            return GetAttributeValue(sourceType, attributeValueAction, name);
        }

        private static string GetAttributeValue<T>(Type sourceType, Func<T, string> attributeValueAction,
            string name) where T : Attribute
        {
            var key = BuildKey(sourceType, name);
            if (!Cache.ContainsKey(key))
            {
                CacheAttributeValue(sourceType, attributeValueAction, name);
            }

            return Cache[key];
        }

        /// <summary>
        /// 快取Attribute Value
        /// </summary>
        private static void CacheAttributeValue<T>(Type type,
            Func<T, string> attributeValueAction, string name)
        {
            var key = BuildKey(type, name);

            var value = GetValue(type, attributeValueAction, name);

            lock (key + "_attributeValueLockKey")
            {
                if (!Cache.ContainsKey(key))
                {
                    Cache[key] = value;
                }
            }
        }

        private static string GetValue<T>(Type type,
            Func<T, string> attributeValueAction, string name)
        {
            object attribute = null;
            if (string.IsNullOrEmpty(name))
            {
                attribute =
                    type.GetCustomAttributes(typeof (T), false).FirstOrDefault();
            }
            else
            {
                var propertyInfo = type.GetProperty(name);
                if (propertyInfo != null)
                {
                    attribute =
                        propertyInfo.GetCustomAttributes(typeof (T), false).FirstOrDefault();
                }

                var fieldInfo = type.GetField(name);
                if (fieldInfo != null)
                {
                    attribute = fieldInfo.GetCustomAttributes(typeof (T), false).FirstOrDefault();
                }
            }

            return attribute == null ? null : attributeValueAction((T) attribute);
        }

        /// <summary>
        /// 快取Collection Name Key
        /// </summary>
        private static string BuildKey(Type type, string name)
        {
            if (string.IsNullOrEmpty(name))
            {
                return type.FullName;
            }

            return type.FullName + "." + name;
        }
    }

var cName=typeof(CustomAttributes).GetCustomAttributeValue<NameAttribute>(x => x.Name);
var fName = typeof (CustomAttributes).GetCustomAttributeValue<NameAttribute>(x => x.Name, "Address");