C# WebBrowser如何清除缓存？

Question

Microsoft Visual Studio 2005 中的webbrowser浏览器为什么当一个账户登录成功后，却再也不能回到登录页面，总是显示登录成功的页面，除非关掉进程，我反复试过，好像是程序把网页页面缓存住了，请问有没有好的解决办法？最好有代码示例。先谢过了。

Answer 1

这个，你没把登录信息写入cookice就不会啊。

Answer 2

那怎样是登录信息不写入Cookie呢？

Answer 3

InternetSetCookieA( 
    IN LPCSTR lpszUrl, 
    IN LPCSTR lpszCookieName, 
    IN LPCSTR lpszCookieData 
    ); 

Answer 4

怎么注销？我重新new 一个新的webbrowser都不行。

Answer 5

你清一下Cookie不行吗？在你new一个的同时。

Answer 6

C# API实现，不知道行不行，共享一下，找了很久才找到的
using System;
using System.Runtime.InteropServices;// Visual C# version of Q326201
namespace Q326201CS
{
    // Class for deleting the cache.
    class DeleteCache
    {
        // 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 FILETIME LastModifiedTime;
            [FieldOffset(40)] public FILETIME ExpireTime;
            [FieldOffset(48)] public FILETIME LastAccessTime;
            [FieldOffset(56)] public 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);        [STAThread]
        static void Main(string[] args)
        {
            // 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)
            {
                // 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));                 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);
        }
    }
}

Answer 7

webbrowser 缓存不能清除。想起他思路吧。

Answer 8

调用RunDll32.exeRunCmd("RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 8");void RunCmd(string cmd)
{
System.Diagnostics.Process p = new System.Diagnostics.Process();
p.StartInfo.FileName = "cmd.exe";
// 关闭Shell的使用
p.StartInfo.UseShellExecute = false;
// 重定向标准输入
p.StartInfo.RedirectStandardInput = true;
// 重定向标准输出
p.StartInfo.RedirectStandardOutput = true;
//重定向错误输出
p.StartInfo.RedirectStandardError = true;
p.StartInfo.CreateNoWindow = true;
p.Start();
p.StandardInput.WriteLine(cmd);
p.StandardInput.WriteLine("exit");
}以下是其他一些参数的说明:
//Temporary Internet Files  （Internet临时文件）
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 8
//Cookies
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 2
//History (历史记录)
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 1
//Form Data （表单数据）
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 16
//Passwords (密码）
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 32
//Delete All  （全部删除）
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 255
//Delete All - "Also delete files and settings stored by add-ons"
//RunDll32.exe InetCpl.cpl,ClearMyTracksByProcess 4351