C#读取IE的Cache

using System;
using System.Runtime.InteropServices;
namespace TimeFound.CTD.ResourceManager
{
    ///

    /// IECache 的摘要说明。
    ///

    public class IECache
    {
        public IECache()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }

  #region 引入所需要的Dll

  [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]
  private struct INTERNET_CACHE_ENTRY_INFO
  {
   public int dwStructSize;
   public IntPtr lpszSourceUrlName;
   public IntPtr lpszLocalFileName;
   public int CacheEntryType;
   public int dwUseCount;
   public int dwHitRate;
   public int dwSizeLow;
   public int dwSizeHigh;
   public FILETIME LastModifiedTime;
   public FILETIME ExpireTime;
   public FILETIME LastAccessTime;
   public FILETIME LastSyncTime;
   public IntPtr lpHeaderInfo;
   public int dwHeaderInfoSize;
   public IntPtr lpszFileExtension;
   public int dwExemptDelta;
  }

  [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]
  private struct SYSTEMTIME
  {
   public short wYear;
   public short wMonth;
   public short wDayOfWeek;
   public short wDay;
   public short wHour;
   public short wMinute;
   public short wSecond;
   public short wMilliseconds;
  }

  
  [DllImport("kernel32.dll",SetLastError=true, CharSet=CharSet.Auto)]
  private static extern int FileTimeToSystemTime(
   IntPtr lpFileTime,
   IntPtr lpSystemTime);

  [DllImport("wininet",SetLastError=true,CharSet=CharSet.Auto,EntryPoint="FindFirstUrlCacheGroup",CallingConvention=CallingConvention.StdCall)]
  private static extern IntPtr FindFirstUrlCacheGroup(
   int dwFlags,
   int dwFilter,
   IntPtr lpSearchCondition,
   int dwSearchCondition,
   ref long lpGroupId,
   IntPtr lpReserved);

[DllImport("wininet",SetLastError=true,CharSet=CharSet.Auto,EntryPoint="FindNextUrlCacheGroup",CallingConvention=CallingConvention.StdCall)]
  private static extern bool FindNextUrlCacheGroup(
   IntPtr hFind,
   ref long lpGroupId,
   IntPtr lpReserved);
  
  [DllImport("wininet", SetLastError=true, CharSet=CharSet.Auto, EntryPoint="DeleteUrlCacheGroup", CallingConvention=CallingConvention.StdCall)]
  private static extern bool DeleteUrlCacheGroup(
   long GroupId,
   int dwFlags,
   IntPtr lpReserved);

  [DllImport("wininet.dll", SetLastError=true, CharSet=CharSet.Auto)]
  private static extern IntPtr FindFirstUrlCacheEntry([MarshalAs(UnmanagedType.LPTStr)] string UrlSearchPattern, IntPtr lpFirstCacheEntryInfo, ref int lpdwFirstCacheEntryInfoBufferSize);

  [DllImport("wininet.dll", SetLastError=true, CharSet=CharSet.Auto)]
 private static extern bool FindNextUrlCacheEntry(
   IntPtr hEnumHandle,
   IntPtr lpNextCacheEntryInfo,
   ref int lpdwNextCacheEntryInfoBufferSize);

  [DllImport("wininet.dll", SetLastError=true, CharSet=CharSet.Auto)]
  private static extern bool GetUrlCacheEntryInfo(
   [MarshalAs(UnmanagedType.LPTStr)] string lpszUrlName,
   IntPtr lpCacheEntryInfo,
   ref int lpdwCacheEntryInfoBufferSize
   );

  [DllImport("wininet.dll")]
  private static extern bool FindCloseUrlCache( IntPtr hEnumHandle);

  [DllImport("wininet",
    SetLastError=true,
    CharSet=CharSet.Auto,
    EntryPoint="DeleteUrlCacheEntryA",
    CallingConvention=CallingConvention.StdCall)]
  private static extern bool DeleteUrlCacheEntry(
   IntPtr lpszUrlName);

  const int ERROR_NO_MORE_ITEMS = 259;
  ///

  /// Retrieves the flags, type, and disk quota attributes of the cache group. This is used by the GetUrlCacheGroupAttribute function.
  ///

  const int CACHEGROUP_ATTRIBUTE_BASIC = 0x00000001;
   ///

  /// Sets or retrieves the flags associated with the cache group. This is used by the GetUrlCacheGroupAttribute and SetUrlCacheGroupAttribute functions.
  ///

  const int CACHEGROUP_ATTRIBUTE_FLAG =0x00000002;
  
   ///

  /// Retrieves all the attributes of the cache group. This is used by the GetUrlCacheGroupAttribute function.
  ///

  const uint CACHEGROUP_ATTRIBUTE_GET_ALL =0xffffffff;
  
   ///

  /// Sets or retrieves the group name of the cache group. This is used by the GetUrlCacheGroupAttribute and SetUrlCacheGroupAttribute functions.
  ///

  const int CACHEGROUP_ATTRIBUTE_GROUPNAME =0x000000010;
  
   ///

  /// Sets or retrieves the disk quota associated with the cache group. This is used by the GetUrlCacheGroupAttribute and SetUrlCacheGroupAttribute functions.
  ///

  const int CACHEGROUP_ATTRIBUTE_QUOTA =0x00000008;
///

  /// Sets or retrieves the group owner storage associated with the cache group. This is used by the GetUrlCacheGroupAttribute and SetUrlCacheGroupAttribute functions.
  ///

  const int CACHEGROUP_ATTRIBUTE_STORAGE =0x00000020;
  
   ///

  /// Sets or retrieves the cache group type. This is used by the GetUrlCacheGroupAttribute and SetUrlCacheGroupAttribute functions.
  ///

  const int CACHEGROUP_ATTRIBUTE_TYPE =0x00000004;
  
   ///

  /// Indicates that all the cache entries associated with the cache group should be deleted, unless the entry belongs to another cache group.
  ///

  const int CACHEGROUP_FLAG_FLUSHURL_ONDELETE =0x00000002;
  
   ///

  /// Indicates that the function should only create a unique GROUPID for the cache group and not create the actual group.
  ///

  const int CACHEGROUP_FLAG_GIDONLY = 0x00000004;
  
   ///

  /// Indicates that the cache group cannot be purged.
  ///

  const int CACHEGROUP_FLAG_NONPURGEABLE =0x00000001;
  
   ///

  /// Sets the type, disk quota, group name, and owner storage attributes of the cache group. This is used by the SetUrlCacheGroupAttribute function.
  ///

  const int CACHEGROUP_READWRITE_MASK =0x0000003c;

 

  ///

  /// Indicates that all of the cache groups in the user"s system should be enumerated.
  ///

  const int CACHEGROUP_SEARCH_ALL =0x00000000;
  
   ///

  /// Not currently implemented.
  ///

  const int CACHEGROUP_SEARCH_BYURL =0x00000001;
  
   ///

  /// Indicates that the cache group type is invalid.
  ///

  const int CACHEGROUP_TYPE_INVALID =0x00000001;
  
   ///

  /// Length of the group owner storage array.
  ///

  const int GROUP_OWNER_STORAGE_SIZE =0x00000004;
  
   ///

  /// Maximum number of characters allowed for a cache group name.
  ///

  const int GROUPNAME_MAX_LENGTH =0x00000078;
#endregion

#region FileTimeToSystemTime

  private string FILETIMEtoDataTime(FILETIME time)
  {
   IntPtr filetime = Marshal.AllocHGlobal( Marshal.SizeOf(typeof(FILETIME)) );
   IntPtr systime = Marshal.AllocHGlobal( Marshal.SizeOf(typeof(SYSTEMTIME)) );
   Marshal.StructureToPtr(time,filetime,true);
   FileTimeToSystemTime( filetime ,systime);
   SYSTEMTIME st = (SYSTEMTIME) Marshal.PtrToStructure(systime,typeof(SYSTEMTIME));
   string Time = st.wYear.ToString()+"."+st.wMonth.ToString()+"."+st.wDay.ToString()+"."+st.wHour.ToString()+"."+st.wMinute.ToString()+"."+st.wSecond.ToString();
   return Time;
  }

#endregion

#region 加载数据

  ///

  /// 获得指定的URL的cache文件名
  ///

  /// URL
  /// 如果不存在该cache，返回空字符串
  public string GetURLCacheFileName(string URL)
  {
   string s="";
   int nNeeded = 0, nBufSize;
   IntPtr buf;
   INTERNET_CACHE_ENTRY_INFO CacheItem;

   FindFirstUrlCacheEntry( null, IntPtr.Zero, ref nNeeded );

   if ( Marshal.GetLastWin32Error() == ERROR_NO_MORE_ITEMS )
    return s;

   nBufSize = nNeeded;
   buf = Marshal.AllocHGlobal( nBufSize );
   GetUrlCacheEntryInfo(URL,buf,ref nNeeded);
   try
   {

    CacheItem = (INTERNET_CACHE_ENTRY_INFO) Marshal.PtrToStructure( buf,typeof(INTERNET_CACHE_ENTRY_INFO) ); 
 
    s=Marshal.PtrToStringAuto(CacheItem.lpszLocalFileName);

/*
以下这一段儿写的有些弱智。。。。但是没有办法。。。。不知道为什么，通过上面的方法取出来的文件的Cache路径，有时候是乱码，有时候用PtrToStringAnsi可是又正常。。。。。唉，所以只能用这个笨办法。。。。

*/ 

   if(s.IndexOf("Temporary Internet Files")==-1)
     s=Marshal.PtrToStringAnsi(CacheItem.lpszLocalFileName); 
    if(s.IndexOf("Temporary Internet Files")==-1)
     s=Marshal.PtrToStringBSTR(CacheItem.lpszLocalFileName); 
    if(s.IndexOf("Temporary Internet Files")==-1)
     s=Marshal.PtrToStringUni(CacheItem.lpszLocalFileName); 

   }
   catch(System.Exception ex)
   {
    Console.WriteLine(ex.Message + ex.StackTrace);
   }

Marshal.FreeHGlobal( buf ); 
   return s;
  }

  public void GetCacheFile()
  {

   int nNeeded = 0, nBufSize;
   IntPtr buf;
   INTERNET_CACHE_ENTRY_INFO CacheItem;
   IntPtr hEnum;
   bool r;

   FindFirstUrlCacheEntry( null, IntPtr.Zero, ref nNeeded );

   if ( Marshal.GetLastWin32Error() == ERROR_NO_MORE_ITEMS )
    return;

   nBufSize = nNeeded;
   buf = Marshal.AllocHGlobal( nBufSize );
   hEnum = FindFirstUrlCacheEntry( null, buf, ref nNeeded );
   while ( true )
   {
    CacheItem = (INTERNET_CACHE_ENTRY_INFO) Marshal.PtrToStructure( buf,
     typeof(INTERNET_CACHE_ENTRY_INFO) );

    string modifiedTime = FILETIMEtoDataTime(CacheItem.LastModifiedTime);
    string expireTime = FILETIMEtoDataTime(CacheItem.ExpireTime);
    string accessTime = FILETIMEtoDataTime(CacheItem.LastAccessTime);
string syncTime = FILETIMEtoDataTime(CacheItem.LastSyncTime);

 

    string s;
#region 获得数据
    try
    {

     s = Marshal.PtrToStringAuto(CacheItem.lpszSourceUrlName) + System.Environment.NewLine  + "  ===> " + Marshal.PtrToStringAuto(CacheItem.lpszLocalFileName) + System.Environment.NewLine+ "  ==> " + Marshal.PtrToStringAuto(CacheItem.lpHeaderInfo)+ System.Environment.NewLine + Marshal.PtrToStringAuto(CacheItem.lpszFileExtension);

     Console.WriteLine(s);
    }
    catch
    {
     
    }
#endregion

    

    nNeeded = nBufSize;
    r = FindNextUrlCacheEntry( hEnum, buf, ref nNeeded );

    if ( !r && Marshal.GetLastWin32Error() == ERROR_NO_MORE_ITEMS )
     break;

    if ( !r && nNeeded > nBufSize )
    {
     nBufSize = nNeeded;
     buf = Marshal.ReAllocHGlobal( buf, (IntPtr) nBufSize );
     FindNextUrlCacheEntry( hEnum, buf, ref nNeeded );
    }
   }

   Marshal.FreeHGlobal( buf );

  }

#endregion

 }
}