我有這段代碼清除C#WebBrowser控件中的緩存。問題在於它也會清除cookie。我似乎是整個互聯網上唯一不想要的人。C#WebBrowser控件:清除緩存但不清除Cookie
我需要維護cookie,但要扔掉緩存。
特別感興趣的是這一行:
const int CACHEGROUP_SEARCH_ALL = 0x0;
似乎確定哪些「緩存組」(赫克無論那些)被清洗出來,我希望餅乾緩存組我可以跳過。然而,試圖找到任何有關這方面的信息只會產生令人頭疼的頭痛。
此代碼最初從MSDN文章拍攝,但它甚至沒有提及餅乾或高速緩存組。
您可以在代碼頂部看到MSDN文章。
/**
* Modified from code originally found here: http://support.microsoft.com/kb/326201
**/
using System;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using System.Diagnostics;
namespace Goop
{
// Class for deleting the cache.
public static class WebBrowserHelper
{
#region Definitions/DLL Imports
// For PInvoke: Contains information about an entry in the Internet cache
[StructLayout(LayoutKind.Explicit, Size = 80)]
public struct INTERNET_CACHE_ENTRY_INFOA
{
[FieldOffset(0)]
public uint dwStructSize;
[FieldOffset(4)]
public IntPtr lpszSourceUrlName;
[FieldOffset(8)]
public IntPtr lpszLocalFileName;
[FieldOffset(12)]
public uint CacheEntryType;
[FieldOffset(16)]
public uint dwUseCount;
[FieldOffset(20)]
public uint dwHitRate;
[FieldOffset(24)]
public uint dwSizeLow;
[FieldOffset(28)]
public uint dwSizeHigh;
[FieldOffset(32)]
public System.Runtime.InteropServices.ComTypes.FILETIME LastModifiedTime;
[FieldOffset(40)]
public System.Runtime.InteropServices.ComTypes.FILETIME ExpireTime;
[FieldOffset(48)]
public System.Runtime.InteropServices.ComTypes.FILETIME LastAccessTime;
[FieldOffset(56)]
public System.Runtime.InteropServices.ComTypes.FILETIME LastSyncTime;
[FieldOffset(64)]
public IntPtr lpHeaderInfo;
[FieldOffset(68)]
public uint dwHeaderInfoSize;
[FieldOffset(72)]
public IntPtr lpszFileExtension;
[FieldOffset(76)]
public uint dwReserved;
[FieldOffset(76)]
public uint dwExemptDelta;
}
// For PInvoke: Initiates the enumeration of the cache groups in the Internet cache
[DllImport(@"wininet",
SetLastError = true,
CharSet = CharSet.Auto,
EntryPoint = "FindFirstUrlCacheGroup",
CallingConvention = CallingConvention.StdCall)]
public static extern IntPtr FindFirstUrlCacheGroup(
int dwFlags,
int dwFilter,
IntPtr lpSearchCondition,
int dwSearchCondition,
ref long lpGroupId,
IntPtr lpReserved);
// For PInvoke: Retrieves the next cache group in a cache group enumeration
[DllImport(@"wininet",
SetLastError = true,
CharSet = CharSet.Auto,
EntryPoint = "FindNextUrlCacheGroup",
CallingConvention = CallingConvention.StdCall)]
public static extern bool FindNextUrlCacheGroup(
IntPtr hFind,
ref long lpGroupId,
IntPtr lpReserved);
// For PInvoke: Releases the specified GROUPID and any associated state in the cache index file
[DllImport(@"wininet",
SetLastError = true,
CharSet = CharSet.Auto,
EntryPoint = "DeleteUrlCacheGroup",
CallingConvention = CallingConvention.StdCall)]
public static extern bool DeleteUrlCacheGroup(
long GroupId,
int dwFlags,
IntPtr lpReserved);
// For PInvoke: Begins the enumeration of the Internet cache
[DllImport(@"wininet",
SetLastError = true,
CharSet = CharSet.Auto,
EntryPoint = "FindFirstUrlCacheEntryA",
CallingConvention = CallingConvention.StdCall)]
public static extern IntPtr FindFirstUrlCacheEntry(
[MarshalAs(UnmanagedType.LPTStr)] string lpszUrlSearchPattern,
IntPtr lpFirstCacheEntryInfo,
ref int lpdwFirstCacheEntryInfoBufferSize);
// For PInvoke: Retrieves the next entry in the Internet cache
[DllImport(@"wininet",
SetLastError = true,
CharSet = CharSet.Auto,
EntryPoint = "FindNextUrlCacheEntryA",
CallingConvention = CallingConvention.StdCall)]
public static extern bool FindNextUrlCacheEntry(
IntPtr hFind,
IntPtr lpNextCacheEntryInfo,
ref int lpdwNextCacheEntryInfoBufferSize);
// For PInvoke: Removes the file that is associated with the source name from the cache, if the file exists
[DllImport(@"wininet",
SetLastError = true,
CharSet = CharSet.Auto,
EntryPoint = "DeleteUrlCacheEntryA",
CallingConvention = CallingConvention.StdCall)]
public static extern bool DeleteUrlCacheEntry(
IntPtr lpszUrlName);
#endregion
#region Public Static Functions
///
/// Clears the cache of the web browser
///
public static void ClearCache()
{
// Indicates that all of the cache groups in the user's system should be enumerated
const int CACHEGROUP_SEARCH_ALL = 0x0;
// Indicates that all the cache entries that are associated with the cache group
// should be deleted, unless the entry belongs to another cache group.
const int CACHEGROUP_FLAG_FLUSHURL_ONDELETE = 0x2;
// File not found.
const int ERROR_FILE_NOT_FOUND = 0x2;
// No more items have been found.
const int ERROR_NO_MORE_ITEMS = 259;
// Pointer to a GROUPID variable
long groupId = 0;
// Local variables
int cacheEntryInfoBufferSizeInitial = 0;
int cacheEntryInfoBufferSize = 0;
IntPtr cacheEntryInfoBuffer = IntPtr.Zero;
INTERNET_CACHE_ENTRY_INFOA internetCacheEntry;
IntPtr enumHandle = IntPtr.Zero;
bool returnValue = false;
// Delete the groups first.
// Groups may not always exist on the system.
// For more information, visit the following Microsoft Web site:
// http://msdn.microsoft.com/library/?url=/workshop/networking/wininet/overview/cache.asp
// By default, a URL does not belong to any group. Therefore, that cache may become
// empty even when the CacheGroup APIs are not used because the existing URL does not belong to any group.
enumHandle = FindFirstUrlCacheGroup(0, CACHEGROUP_SEARCH_ALL, IntPtr.Zero, 0, ref groupId, IntPtr.Zero);
// If there are no items in the Cache, you are finished.
if (enumHandle != IntPtr.Zero && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
{
return;
}
// Loop through Cache Group, and then delete entries.
while (true)
{
if (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error())
{
break;
}
// Delete a particular Cache Group.
returnValue = DeleteUrlCacheGroup(groupId, CACHEGROUP_FLAG_FLUSHURL_ONDELETE, IntPtr.Zero);
if (!returnValue && ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error())
{
returnValue = FindNextUrlCacheGroup(enumHandle, ref groupId, IntPtr.Zero);
}
if (!returnValue && (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error()))
break;
}
// Start to delete URLs that do not belong to any group.
enumHandle = FindFirstUrlCacheEntry(null, IntPtr.Zero, ref cacheEntryInfoBufferSizeInitial);
if (enumHandle != IntPtr.Zero && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
{
return;
}
cacheEntryInfoBufferSize = cacheEntryInfoBufferSizeInitial;
cacheEntryInfoBuffer = Marshal.AllocHGlobal(cacheEntryInfoBufferSize);
enumHandle = FindFirstUrlCacheEntry(null, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
while (true)
{
internetCacheEntry = (INTERNET_CACHE_ENTRY_INFOA)Marshal.PtrToStructure(cacheEntryInfoBuffer, typeof(INTERNET_CACHE_ENTRY_INFOA));
if (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || cacheEntryInfoBufferSize == 0)
{
break;
}
cacheEntryInfoBufferSizeInitial = cacheEntryInfoBufferSize;
returnValue = DeleteUrlCacheEntry(internetCacheEntry.lpszSourceUrlName);
if (!returnValue)
{
returnValue = FindNextUrlCacheEntry(enumHandle, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
}
if (!returnValue && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
{
break;
}
if (!returnValue && cacheEntryInfoBufferSizeInitial > cacheEntryInfoBufferSize)
{
cacheEntryInfoBufferSize = cacheEntryInfoBufferSizeInitial;
cacheEntryInfoBuffer = Marshal.ReAllocHGlobal(cacheEntryInfoBuffer, (IntPtr)cacheEntryInfoBufferSize);
returnValue = FindNextUrlCacheEntry(enumHandle, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
}
}
Marshal.FreeHGlobal(cacheEntryInfoBuffer);
}
#endregion
}
}
任何和所有的幫助非常感謝。
老總岡納森,關於這個問題的任何更新? WebBrowserHelper的代碼中的任何更改? – Kiquenet 2010-07-20 18:46:45
@alhambraeidos:不,我最終運行了一個控制檯命令。大約半秒鐘之後,我把焦點從我的窗戶上取下來,但是對於我的目的來說沒關係。 – Teekin 2010-07-30 16:09:10