C#实现清除IE浏览器缓存的方法
作者：Adam Viki
这篇文章主要介绍了C#实现清除IE浏览器缓存的方法,实例分析了C#针对浏览器缓存清理所涉及的相关技巧,具有一定参考借鉴价值,需要的朋友可以参考下
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> " +
"<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。