通过测试webBrowser与IE缓存和Cookie都存放在Local Settings\Temporary Internet Files，我们可以直接调用IE API进行清除

解决方案1：

public enum ShowCommands : int{SW_HIDE = 0,SW_SHOWNORMAL = 1,SW_NORMAL = 1,SW_SHOWMINIMIZED = 2,SW_SHOWMAXIMIZED = 3,SW_MAXIMIZE = 3,SW_SHOWNOACTIVATE = 4,SW_SHOW = 5,SW_MINIMIZE = 6,SW_SHOWMINNOACTIVE = 7,SW_SHOWNA = 8,SW_RESTORE = 9,SW_SHOWDEFAULT = 10,SW_FORCEMINIMIZE = 11,SW_MAX = 11}

[DllImport("shell32.dll")]static extern IntPtr ShellExecute( IntPtr hwnd, string lpOperation, string lpFile, string lpParameters, string lpDirectory, ShowCommands nShowCmd);

//清除IE临时文件ShellExecute(IntPtr.Zero, "open", "rundll32.exe", " InetCpl.cpl,ClearMyTracksByProcess 255", "", ShowCommands.SW_HIDE);

其中ClearMyTracksByProcess 可进行选择设置 ：

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

解决方案2：快速清除webBrowser Cookie

wb.Document.Cookie.Remove(0, (wb.Document.Cookie.Count - 1))

另外一个

1. [DllImport("wininet.dll", CharSet = System.Runtime.InteropServices.CharSet.Auto, SetLastError = true)]
2. public static extern bool InternetSetOption(int hInternet, int dwOption, IntPtr lpBuffer, int dwBufferLength);
3. private unsafe void SuppressWininetBehavior()
4. {
5. /* SOURCE: http://msdn.microsoft.com/en-us/library/windows/desktop/aa385328%28v=vs.85%29.aspx
6. * INTERNET_OPTION_SUPPRESS_BEHAVIOR (81):
7. * A general purpose option that is used to suppress behaviors on a process-wide basis.
8. * The lpBuffer parameter of the function must be a pointer to a DWORD containing the specific behavior to suppress.
9. * This option cannot be queried with InternetQueryOption.
10. *
11. * INTERNET_SUPPRESS_COOKIE_PERSIST (3):
12. * Suppresses the persistence of cookies, even if the server has specified them as persistent.
13. * Version: Requires Internet Explorer 8.0 or later.
14. */
15. int option = (int)3/* INTERNET_SUPPRESS_COOKIE_PERSIST*/;
16. int* optionPtr = &option;
17. bool success = InternetSetOption(0, 81/*INTERNET_OPTION_SUPPRESS_BEHAVIOR*/, new IntPtr(optionPtr), sizeof(int));
18. if (!success)
19. {
20. MessageBox.Show("Something went wrong !>?");
21. }
22. }