C#实现清除IE浏览器缓存的方法

本文实例讲述了C#实现清除IE浏览器缓存的方法。分享给大家供大家参考。具体如下：

项目中碰到wpf webbrowser的几个问题,在此记录一下

1.webbrowser中对于jquery的bind事件的处理.

在普通的浏览器下一下这种写法没有任何问题

　　var content = $("<div><h4><span>" + category_name + "</span>(<a id='href_" + guid + "' href='AddOrEditShowInfo.aspx?Category=" + guid + "'>添加展示</a>)" +
  "<span id='edit_" + guid + "' style='font-size:12px;cursor:pointer;' onclick='showCategory(this, \""+guid+"\")'>修改分类</span>&nbsp;&nbsp;" +
  "<span id='del_" + guid + "' style='font-size:12px;cursor:pointer;' onclick=delCategory(this, \""+guid+"\")'>删除分类</span></h4>" +
  "<table class='gridview' cellspacing='0' rules='all' border='1' id='gvData' width='100%'>" +
  "<thead><tr><th>缩略图</th><th>展示名称</th><th>简介</th><th>详细描述</th><th>操作</th></tr></thead>" +
  "<tbody id='t_" + guid + "' class='css_tbody'></tbody></table></div>"
);
$("#vtab").append(content);

但是在webbrowser中事件就会不响应,把content中的onclick去掉,在下面这样绑定:

$("#edit_" + guid).unbind("click").bind("click", function () { showCategory(this, guid) });
$("#del_" + guid).unbind("click").bind("click", function () { delCategory(this,guid)});

2.在webbrowser中使用jquery uploadify上传组件的问题

使用该组件的时候 ,发现上传图片的时候 ,第一次上传的时候没有任何问题,第二次上传的时候会出现无法上传的情况,没有任何反应,没有任何错误,上传进度不动,上传的后台代码也不能触发.

解决方案是:清空浏览器缓存就Ok 了.下面就介绍代码清空缓存的方法

3. 清理IE缓存的方法

很明显 IE的缓存在其目录中显示的并不是真正的文件所处的位置,文件的位置是在隐藏的文件夹中,而且这个隐藏的文件夹我们一般找不到.在网上几种清空缓存的方法,在此我一一把代码和处理的效果显示出来.供大家参考.

①.使用ie缓存路径来删除缓存的

string cachePath = Environment.GetFolderPath(Environment.SpecialFolder.InternetCache);
//获取缓存路径
DirectoryInfo di = new DirectoryInfo(cachePath);
foreach (FileInfo fi in di.GetFiles("*.*", SearchOption.AllDirectories))//遍历所有的文件夹 删除里面的文件
{
  try
  {
   fi.Delete();
  }
  catch { }
}

效果:并没有真正的删除缓存文件.而且会出现很多异常,比如enguser.dat,index.dat,,,这些文件删除的时候会出现另一个程序还在使用的错误

②.调用winnet.dll 清理缓存 上代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Rntime.InteropServices;
using System.IO;
namespace WpfClient.AppCode
{
 public class ClearCache
 {
  [StructLayout(LayoutKind.Explicit, Size = 80,CharSet=CharSet.Auto)]
  protected 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)]
  protected 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)]
  protected 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)]
  protected 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)]
  protected 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)]
  protected 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)]
  protected static extern bool DeleteUrlCacheEntry(
   IntPtr lpszUrlName)
  public static void DelCache(){
   // 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);
    string s = Marshal.PtrToStringAnsi(internetCacheEntry.lpszLocalFileName);
    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);  
  }
 }
}

效果:总体来说还是有点效果的,但是效率极低,会出现长时间的等待情况,程序假死. 最重要的是不知道什么时候结束.

③.调用RunDll32.exe

RunCmd("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");
}

效果: 这个方法解决的我的问题,缓存被清空.

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

希望本文所述对大家的C#程序设计有所帮助。