增强版字典DictionaryEx

2019-11-14 16:38:08

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来源：转载

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代码

    public class DictionaryEx<TKey, TValue> : IDictionary<TKey, TValue>    {        /// <summary> 用户存储数据的字典        /// </summary>        PRivate IDictionary<TKey, TValue> _items;        /// <summary> 默认值        /// </summary>        private TValue _defaultValue;        /// <summary> 用于获取值的委托        /// </summary>        private Converter<TKey, TValue> _getValue;        /// <summary> 1返回_defaultValue, 2执行_getValue, 0抛出异常        /// </summary>        private int _mode = 0;        #region 构造函数        /// <summary> 初始化 DictionaryEx , key不存在时返回defaultValue        /// </summary>        /// <param name="defaultValue">默认值</param>        public DictionaryEx(TValue defaultValue)        {            _items = new Dictionary<TKey, TValue>();            _defaultValue = defaultValue;            _mode = 1;        }        /// <summary> 初始化 DictionaryEx , key不存在时返回defaultValue        /// </summary>        /// <param name="defaultValue">默认值</param>        /// <param name="comparer">比较键时要使用对象,如果为null则使用默认比较方法</param>        public DictionaryEx(TValue defaultValue, IEqualityComparer<TKey> comparer)        {            _items = new Dictionary<TKey, TValue>(comparer);            _defaultValue = defaultValue;            _mode = 1;        }        /// <summary> 初始化 DictionaryEx 只读集合, key不存在时返回defaultValue        /// </summary>        /// <param name="defaultValue">默认值</param>        /// <param name="dictionary">内部字典</param>        public DictionaryEx(TValue defaultValue, IDictionary<TKey, TValue> dictionary)        {            Assertor.AreNull(dictionary, "dictionary");            _items = dictionary;            IsReadOnly = true;            _defaultValue = defaultValue;            _mode = 1;        }        /// <summary> 初始化 DictionaryEx, key不存在时返回defaultValue        /// </summary>        /// <param name="defaultValue">默认值</param>        /// <param name="dictionary">内部字典</param>        /// <param name="isReadOnly">是否只读</param>        public DictionaryEx(TValue defaultValue, IDictionary<TKey, TValue> dictionary, bool isReadOnly)        {            Assertor.AreNull(dictionary, "dictionary");            _items = dictionary;            IsReadOnly = isReadOnly;            _defaultValue = defaultValue;            _mode = 1;        }        /// <summary> 初始化 DictionaryEx 设定getValue委托,key不存在时执行委托,并加入集合        /// </summary>        /// <param name="getValue">获取值的委托</param>        public DictionaryEx(Converter<TKey, TValue> getValue)        {            Assertor.AreNull(getValue, "getValue");            _items = new Dictionary<TKey, TValue>();            _getValue = getValue;            _mode = 2;        }        /// <summary> 初始化 DictionaryEx 设定getValue委托,key不存在时执行委托,并加入集合        /// </summary>        /// <param name="getValue">获取值的委托</param>        /// <param name="comparer">比较键时要使用对象,如果为null则使用默认比较方法</param>        public DictionaryEx(Converter<TKey, TValue> getValue, IEqualityComparer<TKey> comparer)        {            Assertor.AreNull(getValue, "getValue");            _items = new Dictionary<TKey, TValue>(comparer);            _getValue = getValue;            _mode = 2;        }        /// <summary> 初始化 DictionaryEx 设定getValue委托,key不存在时执行委托,并加入集合        /// </summary>        /// <param name="getValue">获取值的委托</param>        /// <param name="isReadOnly">集合是否限制外部修改</param>        public DictionaryEx(Converter<TKey, TValue> getValue, bool isReadOnly)        {            Assertor.AreNull(getValue, "getValue");            _items = new Dictionary<TKey, TValue>();            _getValue = getValue;            IsReadOnly = isReadOnly;            _mode = 2;        }        /// <summary> 初始化 DictionaryEx 设定getValue委托,key不存在时执行委托,并加入集合        /// </summary>        /// <param name="getValue">获取值的委托</param>        /// <param name="comparer">比较键时要使用对象</param>        /// <param name="isReadOnly">集合是否限制外部修改</param>        public DictionaryEx(Converter<TKey, TValue> getValue, IEqualityComparer<TKey> comparer, bool isReadOnly)        {            Assertor.AreNull(getValue, "getValue");            _items = new Dictionary<TKey, TValue>(comparer);            _getValue = getValue;            IsReadOnly = isReadOnly;            _mode = 2;        }        /// <summary> 初始化 DictionaryEx 设定getValue委托,key不存在时执行委托,并加入集合        /// </summary>        /// <param name="getValue">获取值的委托</param>        /// <param name="dictionary">内部字典</param>        public DictionaryEx(Converter<TKey, TValue> getValue, IDictionary<TKey, TValue> dictionary)        {            Assertor.AreNull(getValue, "getValue");            Assertor.AreNull(dictionary, "dictionary");            _items = dictionary;            _getValue = getValue;            IsReadOnly = true;            _mode = 2;        }        /// <summary> 初始化 DictionaryEx 设定getValue委托,key不存在时执行委托,并加入集合        /// </summary>        /// <param name="getValue">获取值的委托</param>        /// <param name="dictionary">内部字典</param>        /// <param name="isReadOnly">是否只读</param>        public DictionaryEx(Converter<TKey, TValue> getValue, IDictionary<TKey, TValue> dictionary, bool isReadOnly)        {            _items = dictionary;            _getValue = getValue;            IsReadOnly = isReadOnly;            _mode = 2;        }        /// <summary> 初始化 DictionaryEx 只读集合        /// </summary>        /// <param name="dictionary">内部字典</param>        public DictionaryEx(IDictionary<TKey, TValue> dictionary)        {            Assertor.AreNull(dictionary, "dictionary");            IsReadOnly = true;            _items = dictionary;            _mode = 0;        }        #endregion        private TValue ReturnValue(TKey key)        {            switch (_mode)            {                case 1:                    return _defaultValue;                case 2:                    var value = _getValue(key);                    lock (this)                    {                        _items[key] = value;                    }                    return value;                default:                    throw new KeyNotFoundException();            }        }        public void Add(TKey key, TValue value)        {            this[key] = value;        }        public bool ContainsKey(TKey key)        {            return _items.ContainsKey(key);        }        public ICollection<TKey> Keys        {            get { return _items.Keys; }        }        public bool Remove(TKey key)        {            Assertor.AreTrue(IsReadOnly, "集合为只读");            return _items.Remove(key);        }        public bool TryGetValue(TKey key, out TValue value)        {            return TryGetValue(key, out value);        }        public ICollection<TValue> Values        {            get { return _items.Values; }        }        public TValue this[TKey key]        {            get            {                TValue value;                if (_items.TryGetValue(key, out value))                {                    return value;                }                return ReturnValue(key);            }            set            {                Assertor.AreTrue(IsReadOnly, "集合为只读");                _items[key] = value;            }        }        public void Add(KeyValuePair<TKey, TValue> item)        {            this[item.Key] = item.Value;        }        public void Clear()        {            Assertor.AreTrue(IsReadOnly, "集合为只读");            _items.Clear();        }        public bool Contains(KeyValuePair<TKey, TValue> item)        {            return _items.Contains(item);        }        public void CopyTo(KeyValuePair<TKey, TValue>[] array, int arrayIndex)        {            ((IDictionary<TKey, TValue>)_items).CopyTo(array, arrayIndex);        }        public int Count        {            get { return _items.Count; }        }        public bool IsReadOnly { get; private set; }        public bool Remove(KeyValuePair<TKey, TValue> item)        {            return Remove(item.Key);        }        public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()        {            return _items.GetEnumerator();        }        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()        {            return _items.GetEnumerator();        }    }

View Code

调用

        static void Main(string[] args)        {            //key不存在返回默认值 ,key不区分大小写 (构造函数重载可以设定内部集合,是否只读)            var dict = new DictionaryEx<string, string>("default", StringComparer.OrdinalIgnoreCase);            dict.Add("AAA", "aaa");            Console.WriteLine(dict["aAa"]);  //aaa            Console.WriteLine(dict["Bbb"]);  //default            //key不存在,执行委托,返回value,并加入集合 , 集合本身为只读 (构造函数重载可以设定内部集合,key比较方式)            dict = new DictionaryEx<string, string>(key => "[" + key + "]", true);            Console.WriteLine(dict["Bbb"]); //[Bbb]            try            {                dict["Bbb"] = "newvalue";       //throw new NotSupportedException("集合为只读");            }            catch (Exception) { }            //创建只读键值对集合            var innerDict = new Dictionary<string, string>();            dict = new DictionaryEx<string, string>(innerDict);            innerDict.Add("aaa", "aaa");            Console.WriteLine(dict["aaa"]);            try            {                dict["Bbb"] = "newvalue";       //throw new NotSupportedException("集合为只读");            }            catch (Exception) { }            try            {                Console.WriteLine(dict["bbb"]); //throw new KeyNotFoundException();            }            catch (Exception) { }        }