public static class DictionaryExtensionMethodClass

{

    /// <summary>

    /// 尝试将键和值添加到字典中：如果不存在，才添加；存在，不添加也不抛导常

    /// </summary>

    public static Dictionary<TKey, TValue> TryAdd<TKey, TValue>(this Dictionary<TKey, TValue> dict, TKey key, TValue value)

    {

        if (dict.ContainsKey(key) == false)

            dict.Add(key, value);

        return dict;

    }

    /// <summary>

    /// 将键和值添加或替换到字典中：如果不存在，，则添加；存在，则替换

    /// </summary>

    public static Dictionary<TKey, TValue> AddOrPeplace<TKey, TValue>(this Dictionary<TKey, TValue> dict, TKey key, TValue value)

    {

        dict[key] = value;

        return dict;

    }

    /// <summary>

    /// 获取与指定的键相关联的值，如果没有则返回输入的默认值

    /// </summary>

    public static TValue GetValue<TKey, TValue>(this Dictionary<TKey, TValue> dict, TKey key, TValue defaultValue)

    {

        return dict.ContainsKey(key)?dict[key] : defaultValue;

    }

    /// <summary>

    /// 向字典中批量添加键值对

    /// </summary>

    /// <param>如果已存在，是否替换</param>

    public static Dictionary<TKey, TValue> AddRange<TKey, TValue>(this Dictionary<TKey, TValue> dict, IEnumerable<KeyValuePair<TKey, TValue>> values, bool replaceExisted)

    {

        foreach (var item in values)

        {

            if (dict.ContainsKey(item.Key) == false || replaceExisted)

                dict[item.Key] = item.Value;

        }

        return dict;

    }