对象数据关联扩展

经常会在代码中进行数据关联，比如某张图片点击要打开某个链接。
写了一个扩展，任何对象可以和任何数据关联。

using System.Collections.Generic;
using UnityEngine;

namespace Babybus.Framework.ExtensionMethods
{
    public static class ObjectExtension
    {
        private static Dictionary<object, Dictionary<string, object>> dictionary = new Dictionary<object, Dictionary<string, object>>();

        public static bool HasData(this object obj, string key)
        {
            return dictionary.ContainsKey(obj);
        }

        public static void SetData(this object obj, string key, object value)
        {
            if (!dictionary.ContainsKey(obj))
                dictionary.Add(obj, new Dictionary<string, object>());

            dictionary[obj][key] = value;
        }

        public static T GetData<T>(this object obj, string key, T defaultValue = default(T))
        {
            if (!dictionary.ContainsKey(obj))
                return defaultValue;

            return (T)dictionary[obj][key];
        }

        public static void DeleteData(this object obj, string key)
        {
            if (!dictionary.ContainsKey(obj))
                return;

            var data = dictionary[obj];
            if (data.ContainsKey(key))
                data.Remove(key);
        }

        public static void DeleteAll(this object obj)
        {
            if (dictionary.ContainsKey(obj))
                dictionary.Remove(obj);
        }
    }
}