C# Dictionary拓展

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace CLOU_Comm.Helper
{
    public static class DicExHelper
    {
        public static bool ContainsKeys<TKey, TValue>(this Dictionary<TKey, TValue> dic, List<TKey> keys)
        {
            foreach (var item in keys)
            {
                if (!dic.ContainsKey(item))
                {
                    return false;
                }
            }

            return true;
        }

        public static Dictionary<TKey, TValue> TryAdd<TKey, TValue>(this Dictionary<TKey, TValue> dic, TKey key, TValue value)
        {
            if (!dic.ContainsKey(key))
                dic.Add(key, value);
            return dic;
        }

        public static Dictionary<TKey, TValue> UpdateDic<TKey, TValue>(this Dictionary<TKey, TValue> dest, Dictionary<TKey, TValue> src)
        {
            if (src == null || src.Count() <= 0) return dest;

            foreach (TKey key in src.Keys)
            {
                if (dest.ContainsKey(key))
                {
                    dest[key] = src[key];
                }
                else
                {
                    dest.Add(key, src[key]);
                }

            }
            return dest;
        }
    }
}