Standard Regular Expression Searcher Addin For VS.NET 2003

using System;
using System.Collections.Specialized;
using Microsoft.Win32;

namespace SearcherAddIn
{
	/// <summary>
	/// RecentCache ��ժҪ˵����
	/// </summary>
	public enum CacheType
	{
		Find,
		Replace
	}

	public class RecentCache
	{
		const int _MAX_CACHE_COUNT = 10;
		const string _FIND_KEY = "SOFTWARE\\Niugang\\SearchAddIn\\FindCache";
		const string _SEARCH_KEY = "SOFTWARE\\Niugang\\SearchAddIn\\SearchCache";
		public RecentCache()
		{
			//
			// TODO: �ڴ˴���ӹ��캯���߼�
			//
		}

		private RegistryKey getCacheKey(CacheType cacheType){
			string keyName = cacheType == CacheType.Find?_FIND_KEY:_SEARCH_KEY;
			RegistryKey registryKey = Registry.CurrentUser.OpenSubKey(keyName, true);
			if(registryKey == null)
			{
				registryKey = Registry.CurrentUser.CreateSubKey(keyName);
			}
			return registryKey;
		}

		public StringCollection GetRecentList(CacheType cacheType){
			StringCollection cacheList = new StringCollection();

			RegistryKey registryKey = getCacheKey(cacheType);
			try
			{
				cacheList = new StringCollection();
				for(int i = 1; i <= _MAX_CACHE_COUNT; i++)
				{
					string cache = registryKey.GetValue(cacheType.ToString() + i) as string;
					if(cache != null)
					{
						if(cache.Length > 0)
						{
							cacheList.Add(cache);
						}
					}
				} 
			}
			finally
			{
				registryKey.Close();
			}
			return cacheList;
		}

		public void Add(string content, CacheType cacheType)
		{
			RegistryKey registryKey = getCacheKey(cacheType);
			try
			{
				StringCollection cacheList = GetRecentList(cacheType);
				if(!cacheList.Contains(content))
				{
					if(cacheList.Count == _MAX_CACHE_COUNT)
						cacheList.RemoveAt(0);
					cacheList.Add(content);
				}
				for(int  i = 1; i <= cacheList.Count; i++){
					registryKey.SetValue(cacheType.ToString() + i, cacheList[i - 1]);
				}
			}
			finally
			{
				registryKey.Close();
			}
		}

		public void ClearRecentList(){
			RegistryKey registryKey = getCacheKey(CacheType.Find);
			try
			{
				foreach( string name in registryKey.GetValueNames() )
					registryKey.DeleteValue( name );
			}
			finally
			{
				registryKey.Close();
			}
			
			registryKey = getCacheKey(CacheType.Replace);
			try
			{
				foreach( string name in registryKey.GetValueNames() )
					registryKey.DeleteValue( name );
			}
			finally
			{
				registryKey.Close();
			}
		}

		public string GetCachePattern(CacheType cacheType, int index){
			return GetRecentList(cacheType)[GetRecentList(cacheType).Count - 1 - index];
		}
		
		public bool IsCached(CacheType cacheType, string pattern){
			return GetRecentList(cacheType).Contains(pattern);
		}
	}
}