I am developing a BHO for IE in C# that controls the navigation flow of IE by checking the URL in onBeforeNavigateEvent.
Everything works fine except that when a link is opened in a new tab then some of the tabs opened as About:Blank.
I have checked the logs and also debugged the BHO no exception is thrown. However in the case of About:Blank BHO is initiated SetSite and GetSite methods are called but navigation event is not fired.
Also it happens when links are opened in new tab rapidly.
For testing purpose I disabled the addon and IE worked fine i.e. no About:Blank page.
Loading time of BHO is 0.1s and Navigation time is 0.5s
So, what could be the issue ?
The source I followed to build this BHO is here
Current Environment: IE 11, Windows 10
Interop.cs
using System;
using System.Runtime.InteropServices;
namespace IE_BHO
{
[
ComImport(),
ComVisible(true),
InterfaceType(ComInterfaceType.InterfaceIsIUnknown),
Guid("FC4801A3-2BA9-11CF-A229-00AA003D7352")
]
interface IObjectWithSite
{
[PreserveSig]
int SetSite([In, MarshalAs(UnmanagedType.IUnknown)] object site);
[PreserveSig]
int GetSite(ref Guid guid, out IntPtr ppvSite);
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct OLECMDTEXT
{
public uint cmdtextf;
public uint cwActual;
public uint cwBuf;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 100)]
public char rgwz;
}
[StructLayout(LayoutKind.Sequential)]
public struct OLECMD
{
public uint cmdID;
public uint cmdf;
}
[ComImport(), ComVisible(true),
Guid("B722BCCB-4E68-101B-A2BC-00AA00404770"),
InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IOleCommandTarget
{
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int QueryStatus(
[In] IntPtr pguidCmdGroup,
[In, MarshalAs(UnmanagedType.U4)] uint cCmds,
[In, Out, MarshalAs(UnmanagedType.Struct)] ref OLECMD prgCmds,
//This parameter must be IntPtr, as it can be null
[In, Out] IntPtr pCmdText);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int Exec(
//[In] ref Guid pguidCmdGroup,
//have to be IntPtr, since null values are unacceptable
//and null is used as default group!
[In] IntPtr pguidCmdGroup,
[In, MarshalAs(UnmanagedType.U4)] uint nCmdID,
[In, MarshalAs(UnmanagedType.U4)] uint nCmdexecopt,
[In] IntPtr pvaIn,
[In, Out] IntPtr pvaOut);
}
[Guid("6D5140C1-7436-11CE-8034-00AA006009FA")]
[InterfaceType(1)]
public interface IServiceProvider
{
int QueryService(ref Guid guidService, ref Guid riid, out IntPtr ppvObject);
}
[
ComVisible(true),
Guid("4C1D2E51-018B-4A7C-8A07-618452573E42"),
InterfaceType(ComInterfaceType.InterfaceIsDual)
]
public interface IExtension
{
[DispId(1)]
string ActivateEndPoint(string licenseKey, string userAgent);
}
}
BHO.cs
using Microsoft.Win32;
using SHDocVw;
using System;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.Expando;
using System.Security.Permissions;
using System.Threading.Tasks;
using mshtml;
using System.Reflection;
using System.Diagnostics;
namespace IE_BHO
{
[
SecurityPermission(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode),
ComVisible(true),
Guid("BDCB9FDA-8370-40D9-96C9-9D4B4C25C0D8"),
ClassInterface(ClassInterfaceType.None),
ProgId("myExtension"),
ComDefaultInterface(typeof(IExtension))
]
public class BHO : IObjectWithSite, IOleCommandTarget, IExtension
{
object _site;
IWebBrowser2 _webBrowser2;
#region Implementation of IObjectWithSite
int IObjectWithSite.SetSite(object site)
{
_site = site;
if (site != null)
{
var serviceProv = (IServiceProvider)_site;
var guidIWebBrowserApp = Marshal.GenerateGuidForType(typeof(IWebBrowserApp));
var guidIWebBrowser2 = Marshal.GenerateGuidForType(typeof(IWebBrowser2));
IntPtr intPtr;
serviceProv.QueryService(ref guidIWebBrowserApp, ref guidIWebBrowser2, out intPtr);
_webBrowser2 = (IWebBrowser2)Marshal.GetObjectForIUnknown(intPtr);
((DWebBrowserEvents2_Event)_webBrowser2).BeforeNavigate2 += OnBeforeNavigate2;
((DWebBrowserEvents2_Event)_webBrowser2).BeforeScriptExecute += S2_BeforeScriptExecute;
((DWebBrowserEvents2_Event)_webBrowser2).DownloadComplete += BHO_DownloadComplete;
}
else
{
((DWebBrowserEvents2_Event)_webBrowser2).BeforeNavigate2 -= OnBeforeNavigate2;
((DWebBrowserEvents2_Event)_webBrowser2).BeforeScriptExecute -= S2_BeforeScriptExecute;
((DWebBrowserEvents2_Event)_webBrowser2).DownloadComplete -= BHO_DownloadComplete;
_webBrowser2 = null;
}
return 0;
}
int IObjectWithSite.GetSite(ref Guid guid, out IntPtr ppvSite)
{
IntPtr punk = Marshal.GetIUnknownForObject(_webBrowser2);
int hr = Marshal.QueryInterface(punk, ref guid, out ppvSite);
Marshal.Release(punk);
return hr;
}
public void OnBeforeNavigate2(object pDisp, ref object URL, ref object Flags, ref object TargetFrameName, ref object PostData, ref object Headers, ref bool Cancel)
{
try
{
UrlObj dto = UrlManager.CheckUrl(URL.ToString());
if (dto.IsInList)
{
Cancel = true;
_webBrowser2.Navigate2("www.google.com");
}
}
catch (Exception ex)
{
}
}
private void S2_BeforeScriptExecute(object pDispWindow)
{
ExposeMethodstoJS();
}
private void BHO_DownloadComplete()
{
ExposeMethodstoJS();
}
private void ExposeMethodstoJS(string calledBy)
{
try
{
HTMLDocument doc = _webBrowser.Document as HTMLDocument;
if (doc != null)
{
IHTMLWindow2 tmpWindow = doc.parentWindow;
dynamic window = tmpWindow;
IExpando windowEx = (IExpando)window;
PropertyInfo p = windowEx.AddProperty("myExtension");
p.SetValue(windowEx, this);
}
}
catch (Exception ex)
{
}
}
#endregion
#region Implementation of IOleCommandTarget
int IOleCommandTarget.QueryStatus(IntPtr pguidCmdGroup, uint cCmds, ref OLECMD prgCmds, IntPtr pCmdText)
{
return 0;
}
int IOleCommandTarget.Exec(IntPtr pguidCmdGroup, uint nCmdID, uint nCmdexecopt, IntPtr pvaIn, IntPtr pvaOut)
{
return 0;
}
#endregion
#region Implementation of IExtension
string IExtension.GetDetails()
{
return "Methods Exposed";
}
#endregion
#region COMRegistration
[ComRegisterFunction]
public static void RegisterBHO(Type type)
{
RegistryKey registryKey = Registry.LocalMachine.CreateSubKey(#"Software\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects");
RegistryKey guidKey = registryKey.CreateSubKey(type.GUID.ToString("B"));
registryKey.Close();
guidKey.Close();
}
[ComUnregisterFunction]
public static void UnregisterBHO(Type type)
{
RegistryKey registryKey = Registry.LocalMachine.OpenSubKey(#"Software\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects", true);
string guid = type.GUID.ToString("B");
if (registryKey != null)
{
registryKey.DeleteSubKey(guid, false);
}
}
#endregion COMRegistration
}
}
Which version of IE and OS are you using?
I think the issue occurs because the new tab is opened and navigated at almost the same time. For the detailed information, you could refer to this link.
You could also try the resolution in the article: Install the most recent cumulative security update for Internet Explorer.
Related
I need to confirm programatically (i.e, answer 'yes') to a script error dialog box into WebBrowser otherwise the page will stop working. I have no code to show because I have no idea how I could do this.
Here's a image from dialog box I'm talking about:
(take from this, btw)
According to the "How to handle script errors as a WebBrowser control host" MSKB article, you need to handle CGID_DocHostCommandHandler/OLECMDID_SHOWSCRIPTERROR command in the WebBrowser host.
With a bit of coding, here is how it can be done for the WinForms WebBrowser version, and it actually works:
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public class WebBrowserEx: WebBrowser
{
class WebBrowserSiteEx : WebBrowserSite, NativeMethods.IOleCommandTarget
{
public WebBrowserSiteEx(WebBrowser browser): base(browser)
{
}
public int QueryStatus(IntPtr pguidCmdGroup, uint cCmds, NativeMethods.OLECMD[] prgCmds, ref NativeMethods.OLECMDTEXT CmdText)
{
return NativeMethods.OLECMDERR_E_UNKNOWNGROUP;
}
public int Exec(IntPtr pguidCmdGroup, uint nCmdId, uint nCmdExecOpt, IntPtr pvaIn, IntPtr pvaOut)
{
if (pguidCmdGroup != IntPtr.Zero)
{
Guid guid = (Guid)Marshal.PtrToStructure(pguidCmdGroup, typeof(Guid));
if (guid == NativeMethods.CGID_DocHostCommandHandler)
{
if (nCmdId == NativeMethods.OLECMDID_SHOWSCRIPTERROR)
{
// if DOM needed: dynamic document = Marshal.GetObjectForNativeVariant(pvaIn);
// continue running scripts
if (pvaOut != IntPtr.Zero)
Marshal.GetNativeVariantForObject(true, pvaOut);
return NativeMethods.S_OK;
}
}
}
return NativeMethods.OLECMDERR_E_UNKNOWNGROUP;
}
}
protected override WebBrowserSiteBase CreateWebBrowserSiteBase()
{
return new WebBrowserSiteEx(this);
}
}
public partial class Form1 : Form
{
WebBrowserEx _browser;
public Form1()
{
InitializeComponent();
_browser = new WebBrowserEx();
_browser.Dock = DockStyle.Fill;
this.Controls.Add(_browser);
}
private void Form1_Load(object sender, EventArgs e)
{
// testing
_browser.DocumentText = "<script>alert(bad.bad)</script>";
}
}
static class NativeMethods
{
[StructLayout(LayoutKind.Sequential)]
public struct OLECMD
{
public uint cmdID;
public uint cmdf;
}
[StructLayout(LayoutKind.Sequential)]
public struct OLECMDTEXT
{
public UInt32 cmdtextf;
public UInt32 cwActual;
public UInt32 cwBuf;
public char rgwz;
}
public const int OLECMDERR_E_UNKNOWNGROUP = unchecked((int)0x80040102);
public const int OLECMDID_SHOWSCRIPTERROR = 40;
public static readonly Guid CGID_DocHostCommandHandler = new Guid("f38bc242-b950-11d1-8918-00c04fc2c836");
public const int S_OK = 0;
[ComImport, Guid("b722bccb-4e68-101b-a2bc-00aa00404770"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IOleCommandTarget
{
[PreserveSig]
int QueryStatus(
IntPtr pguidCmdGroup,
UInt32 cCmds,
[In, Out, MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] OLECMD[] prgCmds,
ref OLECMDTEXT CmdText);
[PreserveSig]
int Exec(
IntPtr pguidCmdGroup,
uint nCmdId,
uint nCmdExecOpt,
IntPtr pvaIn,
IntPtr pvaOut);
}
}
}
Updated to address the comment:
I need to capture the JavaScript error info in order to log it while
still not displaying it to the user. I looked at the document object
(the commented out line) and didn't see anything there. Is there an
easy way to capture this info?
Check the article I linked at the beginning. There are special properties errorLine, errorCharacter, errorCode, errorMessage, errorUrl available on document.parentWindow.event object.
I'm working on a WPF app which allows user to drag and drop files from Windows Explorer. For normal files, I'm able to access the path using
string[] fileNames = (string[])e.Data.GetData(DataFormats.FileDrop, false);
But for WPD files, its returning null. Have tried to follow the solution given in http://us.generation-nt.com/answer/drag-drop-pictures-wpd-camera-help-31497882.html#r , but i couldn't make it work. I'm getting AccessVoilationException when trying to get the count of items from the Shell array. I have posted the question in MSDN(http://social.msdn.microsoft.com/Forums/vstudio/en-US/ef7fc152-dd1b-4774-adb7-47b48726daea/drag-drop-from-windows-portable-device-to-wpf-application?forum=wpf), but didn't get any leads.
Is there something that I'm missing here? Could you please help me solve this issue?
Following is the relevant part my code.
public enum SIGDN : uint
{
NORMALDISPLAY = 0,
PARENTRELATIVEPARSING = 0x80018001,
PARENTRELATIVEFORADDRESSBAR = 0x8001c001,
DESKTOPABSOLUTEPARSING = 0x80028000,
PARENTRELATIVEEDITING = 0x80031001,
DESKTOPABSOLUTEEDITING = 0x8004c000,
FILESYSPATH = 0x80058000,
URL = 0x80068000
}
internal class IIDGuid
{
private IIDGuid() { } // Avoid FxCop violation AvoidUninstantiatedInternalClasses
// IID GUID strings for relevant COM interfaces
internal const string IModalWindow = "b4db1657-70d7-485e-8e3e-6fcb5a5c1802";
internal const string IFileDialog = "42f85136-db7e-439c-85f1-e4075d135fc8";
internal const string IFileOpenDialog = "d57c7288-d4ad-4768-be02-9d969532d960";
internal const string IFileSaveDialog = "84bccd23-5fde-4cdb-aea4-af64b83d78ab";
internal const string IFileDialogEvents = "973510DB-7D7F-452B-8975-74A85828D354";
internal const string IShellItem = "43826D1E-E718-42EE-BC55-A1E261C37BFE";
internal const string IShellItemArray = "B63EA76D-1F85-456F-A19C-48159EFA858B";
}
[ComImport]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
[Guid("43826d1e-e718-42ee-bc55-a1e261c37bfe")]
public interface IShellItem
{
void BindToHandler(IntPtr pbc,
[MarshalAs(UnmanagedType.LPStruct)]Guid bhid,
[MarshalAs(UnmanagedType.LPStruct)]Guid riid,
out IntPtr ppv);
void GetParent(out IShellItem ppsi);
void GetDisplayName(SIGDN sigdnName, out IntPtr ppszName);
void GetAttributes(uint sfgaoMask, out uint psfgaoAttribs);
void Compare(IShellItem psi, uint hint, out int piOrder);
};
[ComImport]
[Guid(IIDGuid.IShellItemArray)]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IShellItemArray
{
// Not supported: IBindCtx
void BindToHandler([In, MarshalAs(UnmanagedType.Interface)] IntPtr pbc, [In] ref Guid rbhid, [In] ref Guid riid, out IntPtr ppvOut);
void GetPropertyStore([In] int Flags, [In] ref Guid riid, out IntPtr ppv);
void GetCount(out uint pdwNumItems);
void GetItemAt([In] uint dwIndex, [MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);
void EnumItems([MarshalAs(UnmanagedType.Interface)] out IntPtr ppenumShellItems);
}
[DllImport("shell32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
static extern int SHCreateShellItemArrayFromDataObject(
System.Runtime.InteropServices.ComTypes.IDataObject pdo,
ref Guid riid,
[MarshalAs(UnmanagedType.Interface)] out IShellItemArray ppv);
[DllImport("kernel32.dll", SetLastError = true)]
static extern Int32 GetLastError();
private void OnFileDrop(object sender, DragEventArgs e)
{
string[] fileNames = (string[])e.Data.GetData(DataFormats.FileDrop, false);// null
System.Runtime.InteropServices.ComTypes.IDataObject mydata = e.Data as System.Runtime.InteropServices.ComTypes.IDataObject;
IShellItemArray nativeShellItemArray;
Guid guid = new Guid(IIDGuid.IShellItemArray);
int retCode = SHCreateShellItemArrayFromDataObject(mydata, ref guid, out nativeShellItemArray);
IShellItem nativeShellItem;
if (retCode == 0)
{
IntPtr displayname;
uint items = 0;
try
{
nativeShellItemArray.GetCount(out items); //Getting AccessVoilationException in this line
}
catch (Exception ex)
{
}
if (items > 0)
{
for (uint item = 0; item < items; item++)
{
nativeShellItemArray.GetItemAt(item, out nativeShellItem);
nativeShellItem.GetDisplayName(SIGDN.DESKTOPABSOLUTEPARSING, out displayname);
//Do something
}
}
}
}
I want to intercept drag&drop action on WebBrowser control. To be more precise, I want to be able to cancel or approve drag&drop event based on file extension (and process that file outside WebBrowser) and I want to make drag&drop icon look like regular icon: http://snag.gy/DUjMc.jpg, not like this one: http://snag.gy/ExX19.jpg.
I believe for this I need to implement custom IDocHostUIHandler and intercept GetDropTarget. Unfortunately, I have no success in doing that. I am using this code as my 'base' code: https://stackoverflow.com/a/19739699/2758677 and this part, that I made: http://pastebin.com/Ux947Eck. GetDropTarget is never called.
Here's a complete WinForms-based example that works, IDocHostUIHandler.GetDropTarget does get called.
using System;
using System.Diagnostics;
using System.Linq;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace CustomWebBrowser
{
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
private void MainForm_Load(object sender, EventArgs e)
{
var wb = new ImprovedWebBrowser();
wb.Dock = DockStyle.Fill;
this.Controls.Add(wb);
wb.Visible = true;
wb.DocumentText = "<body contentEditable='true'><b>Hello from ImprovedWebBrowser!</b></body>";
}
}
public class ImprovedWebBrowser : WebBrowser
{
/// <summary>
/// provide custom WebBrowserSite,
/// where we override IDocHostUIHandler and call the base implementation
/// More info: http://stackoverflow.com/a/19739699/1768303
/// </summary>
protected override WebBrowserSiteBase CreateWebBrowserSiteBase()
{
return new ImprovedWebBrowserSite(this);
}
#region ImprovedWebBrowserSite
[ClassInterface(ClassInterfaceType.None)]
protected class ImprovedWebBrowserSite :
WebBrowserSite,
NativeMethods.IDocHostUIHandler,
IDisposable,
ICustomQueryInterface
{
ImprovedWebBrowser _host;
NativeMethods.IDocHostUIHandler _baseIDocHostUIHandler;
IntPtr _unkInnerAggregated;
IntPtr _unkOuter;
Inner _inner;
// constructor
public ImprovedWebBrowserSite(WebBrowser host) :
base(host)
{
_host = (ImprovedWebBrowser)host;
// get the CCW object for this
_unkOuter = Marshal.GetIUnknownForObject(this);
Marshal.AddRef(_unkOuter);
try
{
// aggregate the CCW object with the helper Inner object
_inner = new Inner(this);
_unkInnerAggregated = Marshal.CreateAggregatedObject(_unkOuter, _inner);
// obtain private WebBrowserSite COM interfaces
_baseIDocHostUIHandler = (NativeMethods.IDocHostUIHandler)Marshal.GetTypedObjectForIUnknown(_unkInnerAggregated, typeof(NativeMethods.IDocHostUIHandler));
}
finally
{
Marshal.Release(_unkOuter);
}
}
~ImprovedWebBrowserSite()
{
// need to work out the reference counting for GC to work correctly
Debug.Print("ImprovedWebBrowserSite object finalized.");
}
void IDisposable.Dispose()
{
base.Dispose();
_baseIDocHostUIHandler = null;
if (_unkInnerAggregated != IntPtr.Zero)
{
Marshal.Release(_unkInnerAggregated);
_unkInnerAggregated = IntPtr.Zero;
}
if (_unkOuter != IntPtr.Zero)
{
Marshal.Release(_unkOuter);
_unkOuter = IntPtr.Zero;
}
}
#region Inner
// Inner as aggregated object
class Inner :
ICustomQueryInterface,
IDisposable
{
object _outer;
Type[] _interfaces;
public Inner(object outer)
{
_outer = outer;
_interfaces = _outer.GetType().BaseType.GetInterfaces();
}
public CustomQueryInterfaceResult GetInterface(ref Guid iid, out IntPtr ppv)
{
if (_outer != null)
{
var guid = iid;
var iface = _interfaces.FirstOrDefault((t) => t.GUID == guid);
if (iface != null)
{
var unk = Marshal.GetComInterfaceForObject(_outer, iface, CustomQueryInterfaceMode.Ignore);
if (unk != IntPtr.Zero)
{
ppv = unk;
return CustomQueryInterfaceResult.Handled;
}
}
}
ppv = IntPtr.Zero;
return CustomQueryInterfaceResult.Failed;
}
~Inner()
{
// need to work out the reference counting for GC to work correctly
Debug.Print("Inner object finalized.");
}
public void Dispose()
{
_outer = null;
_interfaces = null;
}
}
#endregion
#region ICustomQueryInterface
public CustomQueryInterfaceResult GetInterface(ref Guid iid, out IntPtr ppv)
{
// CustomQueryInterfaceMode.Ignore is to avoid infinite loop during QI.
if (iid == typeof(NativeMethods.IDocHostUIHandler).GUID)
{
ppv = Marshal.GetComInterfaceForObject(this, typeof(NativeMethods.IDocHostUIHandler), CustomQueryInterfaceMode.Ignore);
}
else
{
ppv = IntPtr.Zero;
return CustomQueryInterfaceResult.NotHandled;
}
return CustomQueryInterfaceResult.Handled;
}
#endregion
#region IDocHostUIHandler
int NativeMethods.IDocHostUIHandler.ShowContextMenu(int dwID, ref NativeMethods.POINT pt, IntPtr pcmdtReserved, IntPtr pdispReserved)
{
return _baseIDocHostUIHandler.ShowContextMenu(dwID, ref pt, pcmdtReserved, pdispReserved);
}
int NativeMethods.IDocHostUIHandler.GetHostInfo(ref NativeMethods.DOCHOSTUIINFO info)
{
Debug.Print("IDocHostUIHandler.GetHostInfo");
return _baseIDocHostUIHandler.GetHostInfo(ref info);
}
int NativeMethods.IDocHostUIHandler.ShowUI(int dwID, IntPtr activeObject, IntPtr commandTarget, IntPtr frame, IntPtr doc)
{
return _baseIDocHostUIHandler.ShowUI(dwID, activeObject, commandTarget, frame, doc);
}
int NativeMethods.IDocHostUIHandler.HideUI()
{
return _baseIDocHostUIHandler.HideUI();
}
int NativeMethods.IDocHostUIHandler.UpdateUI()
{
return _baseIDocHostUIHandler.UpdateUI();
}
int NativeMethods.IDocHostUIHandler.EnableModeless(bool fEnable)
{
return _baseIDocHostUIHandler.EnableModeless(fEnable);
}
int NativeMethods.IDocHostUIHandler.OnDocWindowActivate(bool fActivate)
{
return _baseIDocHostUIHandler.OnDocWindowActivate(fActivate);
}
int NativeMethods.IDocHostUIHandler.OnFrameWindowActivate(bool fActivate)
{
return _baseIDocHostUIHandler.OnFrameWindowActivate(fActivate);
}
int NativeMethods.IDocHostUIHandler.ResizeBorder(ref NativeMethods.COMRECT rect, IntPtr doc, bool fFrameWindow)
{
return _baseIDocHostUIHandler.ResizeBorder(ref rect, doc, fFrameWindow);
}
int NativeMethods.IDocHostUIHandler.TranslateAccelerator(ref NativeMethods.MSG msg, ref Guid group, int nCmdID)
{
return _baseIDocHostUIHandler.TranslateAccelerator(ref msg, ref group, nCmdID);
}
int NativeMethods.IDocHostUIHandler.GetOptionKeyPath(string[] pbstrKey, int dw)
{
return _baseIDocHostUIHandler.GetOptionKeyPath(pbstrKey, dw);
}
int NativeMethods.IDocHostUIHandler.GetDropTarget(IntPtr pDropTarget, out IntPtr ppDropTarget)
{
Debug.Print("IDocHostUIHandler.GetDropTarget");
return _baseIDocHostUIHandler.GetDropTarget(pDropTarget, out ppDropTarget);
}
int NativeMethods.IDocHostUIHandler.GetExternal(out object ppDispatch)
{
return _baseIDocHostUIHandler.GetExternal(out ppDispatch);
}
int NativeMethods.IDocHostUIHandler.TranslateUrl(int dwTranslate, string strURLIn, out string pstrURLOut)
{
return _baseIDocHostUIHandler.TranslateUrl(dwTranslate, strURLIn, out pstrURLOut);
}
int NativeMethods.IDocHostUIHandler.FilterDataObject(IntPtr pDO, out IntPtr ppDORet)
{
return _baseIDocHostUIHandler.FilterDataObject(pDO, out ppDORet);
}
#endregion
}
#endregion
}
public static class NativeMethods
{
#region IDocHostUIHandler
public enum DOCHOSTUIDBLCLICK
{
DEFAULT = 0x0,
SHOWPROPERTIES = 0x1,
SHOWCODE = 0x2
}
public enum DOCHOSTUIFLAG
{
DIALOG = 0x1,
DISABLE_HELP_MENU = 0x2,
NO3DBORDER = 0x4,
SCROLL_NO = 0x8,
DISABLE_SCRIPT_INACTIVE = 0x10,
OPENNEWWIN = 0x20,
DISABLE_OFFSCREEN = 0x40,
FLAT_SCROLLBAR = 0x80,
DIV_BLOCKDEFAULT = 0x100,
ACTIVATE_CLIENTHIT_ONLY = 0x200,
NO3DOUTERBORDER = 0x00200000,
THEME = 0x00040000,
NOTHEME = 0x80000,
DISABLE_COOKIE = 0x400
}
[StructLayout(LayoutKind.Sequential)]
public struct DOCHOSTUIINFO
{
[MarshalAs(UnmanagedType.U4)]
public int cbSize;
[MarshalAs(UnmanagedType.I4)]
public int dwFlags;
[MarshalAs(UnmanagedType.I4)]
public int dwDoubleClick;
[MarshalAs(UnmanagedType.I4)]
public int dwReserved1;
[MarshalAs(UnmanagedType.I4)]
public int dwReserved2;
}
[StructLayout(LayoutKind.Sequential)]
public struct COMRECT
{
public int left;
public int top;
public int right;
public int bottom;
}
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
public int x;
public int y;
}
[StructLayout(LayoutKind.Sequential)]
public struct MSG
{
public IntPtr hwnd;
public int message;
public IntPtr wParam;
public IntPtr lParam;
public int time;
POINT pt;
}
[ComImport(), Guid("BD3F23C0-D43E-11CF-893B-00AA00BDCE1A"),
InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IDocHostUIHandler
{
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int ShowContextMenu(
[In, MarshalAs(UnmanagedType.U4)]
int dwID,
[In]
ref POINT pt,
[In]
IntPtr pcmdtReserved,
[In]
IntPtr pdispReserved);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetHostInfo(
[In, Out]
ref DOCHOSTUIINFO info);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int ShowUI(
[In, MarshalAs(UnmanagedType.I4)]
int dwID,
[In]
IntPtr activeObject,
[In]
IntPtr commandTarget,
[In]
IntPtr frame,
[In]
IntPtr doc);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int HideUI();
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int UpdateUI();
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int EnableModeless(
[In, MarshalAs(UnmanagedType.Bool)]
bool fEnable);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int OnDocWindowActivate(
[In, MarshalAs(UnmanagedType.Bool)]
bool fActivate);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int OnFrameWindowActivate(
[In, MarshalAs(UnmanagedType.Bool)]
bool fActivate);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int ResizeBorder(
[In]
ref COMRECT rect,
[In]
IntPtr doc,
bool fFrameWindow);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int TranslateAccelerator(
[In]
ref MSG msg,
[In]
ref Guid group,
[In, MarshalAs(UnmanagedType.I4)]
int nCmdID);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetOptionKeyPath(
[Out, MarshalAs(UnmanagedType.LPArray)]
String[] pbstrKey,
[In, MarshalAs(UnmanagedType.U4)]
int dw);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetDropTarget(
[In]
IntPtr pDropTarget,
[Out]
out IntPtr ppDropTarget);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetExternal(
[Out, MarshalAs(UnmanagedType.IDispatch)]
out object ppDispatch);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int TranslateUrl(
[In, MarshalAs(UnmanagedType.U4)]
int dwTranslate,
[In, MarshalAs(UnmanagedType.LPWStr)]
string strURLIn,
[Out, MarshalAs(UnmanagedType.LPWStr)]
out string pstrURLOut);
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int FilterDataObject(
[In]
IntPtr pDO,
[Out]
out IntPtr ppDORet);
}
#endregion
}
}
I'm creating a console application that is able to remotely capture screenshots of websites. Everything is working except the fact that I can't avoid Certificate errors. Every time I get popup message that I'm unable to pass.
I tried using:
ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(ValidateServerCertificate);
But it doesn't work.
Also tried the solution found here:
http://www.codeproject.com/Articles/31163/Suppressing-Hosted-WebBrowser-Control-Dialogs
but but it doesnt seem to work for webbrowser invoked from console application.
Any ideas?
The webbrowser control uses WinInet as its network stack. Setting the ServerCertificateValidationCallback would have no effect on WinInet.
To handle the certificate error, you need to implement an IHttpSecurity service and pass to the webbrowser on request. The webbrowser queries host services via IServiceProvider implemented on the ActiveX host. Assuming you are using Windows Forms, you need to do the following:
derive a class from WebBrowser
create a nested class derived from WebBrowser.WebBrowserSite (the only way you can derive from the nested class)
overwrite CreateWebBrowserSiteBase and return a new instance of your webbrowser site.
implement IServiceProvider on the webbrowser site
implement IServiceProvider.QueryService so it returns an IHttpSecurity imepleemntation when the IHttpSecurity service is requested
handle IHttpSecurity.OnSecurityProblem and return S_OK
use the new webbrowser in the form
Example code:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void webBrowser1_DocumentCompleted(object sender,
WebBrowserDocumentCompletedEventArgs e)
{
if (e.Url.ToString() == "about:blank")
{
//create a certificate mismatch
webBrowser1.Navigate("https://74.125.225.229");
}
}
}
[Guid("6D5140C1-7436-11CE-8034-00AA006009FA")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
[ComImport]
public interface UCOMIServiceProvider
{
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int QueryService(
[In] ref Guid guidService,
[In] ref Guid riid,
[Out] out IntPtr ppvObject);
}
[ComImport()]
[ComVisible(true)]
[Guid("79eac9d5-bafa-11ce-8c82-00aa004ba90b")]
[InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IWindowForBindingUI
{
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetWindow(
[In] ref Guid rguidReason,
[In, Out] ref IntPtr phwnd);
}
[ComImport()]
[ComVisible(true)]
[Guid("79eac9d7-bafa-11ce-8c82-00aa004ba90b")]
[InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IHttpSecurity
{
//derived from IWindowForBindingUI
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetWindow(
[In] ref Guid rguidReason,
[In, Out] ref IntPtr phwnd);
[PreserveSig]
int OnSecurityProblem(
[In, MarshalAs(UnmanagedType.U4)] uint dwProblem);
}
public class MyWebBrowser : WebBrowser
{
public static Guid IID_IHttpSecurity
= new Guid("79eac9d7-bafa-11ce-8c82-00aa004ba90b");
public static Guid IID_IWindowForBindingUI
= new Guid("79eac9d5-bafa-11ce-8c82-00aa004ba90b");
public const int S_OK = 0;
public const int S_FALSE = 1;
public const int E_NOINTERFACE = unchecked((int)0x80004002);
public const int RPC_E_RETRY = unchecked((int)0x80010109);
protected override WebBrowserSiteBase CreateWebBrowserSiteBase()
{
return new MyWebBrowserSite(this);
}
class MyWebBrowserSite : WebBrowserSite,
UCOMIServiceProvider,
IHttpSecurity,
IWindowForBindingUI
{
private MyWebBrowser myWebBrowser;
public MyWebBrowserSite(MyWebBrowser myWebBrowser)
:base(myWebBrowser)
{
this.myWebBrowser = myWebBrowser;
}
public int QueryService(ref Guid guidService
, ref Guid riid
, out IntPtr ppvObject)
{
if (riid ==IID_IHttpSecurity)
{
ppvObject= Marshal.GetComInterfaceForObject(this
, typeof(IHttpSecurity));
return S_OK;
}
if (riid == IID_IWindowForBindingUI)
{
ppvObject = Marshal.GetComInterfaceForObject(this
, typeof(IWindowForBindingUI));
return S_OK;
}
ppvObject = IntPtr.Zero;
return E_NOINTERFACE;
}
public int GetWindow(ref Guid rguidReason
, ref IntPtr phwnd)
{
if (rguidReason == IID_IHttpSecurity
|| rguidReason == IID_IWindowForBindingUI)
{
phwnd = myWebBrowser.Handle;
return S_OK;
}
else
{
phwnd = IntPtr.Zero;
return S_FALSE;
}
}
public int OnSecurityProblem(uint dwProblem)
{
//ignore errors
//undocumented return code, does not work on IE6
return S_OK;
}
}
}
Figured it out finally.
I've been trying to bypass the SSL cert error for a Headless IE browser running as a console app (http://triflejs.org)
ShengJiang provided the bulk of the answer but I still couldn't use Application.Run() as it locks up execution on the main thread and I needed to execute other events in the loop, also, instantiating an ApplicationContext with message pumps seemed way too complicated.
The answer once I got it was exceedingly simple. Just create a loop and run Application.DoEvents()
Here is some working code. I simplified it to suit the question posted here.
Please make sure that:
You are running as a Console Application project.
You add a project reference to System.Windows.Forms.
Hope it helps!
using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace IgnoreSSLErrorBrowserConsoleApp
{
public class Program
{
[STAThread]
public static void Main(string[] args)
{
MyWebBrowser browser = new MyWebBrowser();
browser.Navigate("about:blank");
browser.DocumentCompleted += delegate (object obj, WebBrowserDocumentCompletedEventArgs e) {
if (e.Url.ToString() == "about:blank") {
// This is the SSL path where certificate error occurs
browser.Navigate("https://localhost");
}
};
while (browser.ReadyState != WebBrowserReadyState.Complete) {
Application.DoEvents();
// RunOtherEvents();
}
}
}
[Guid("6D5140C1-7436-11CE-8034-00AA006009FA")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
[ComImport]
public interface UCOMIServiceProvider
{
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int QueryService(
[In] ref Guid guidService,
[In] ref Guid riid,
[Out] out IntPtr ppvObject);
}
[ComImport()]
[ComVisible(true)]
[Guid("79eac9d5-bafa-11ce-8c82-00aa004ba90b")]
[InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IWindowForBindingUI
{
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetWindow(
[In] ref Guid rguidReason,
[In, Out] ref IntPtr phwnd);
}
[ComImport()]
[ComVisible(true)]
[Guid("79eac9d7-bafa-11ce-8c82-00aa004ba90b")]
[InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IHttpSecurity
{
//derived from IWindowForBindingUI
[return: MarshalAs(UnmanagedType.I4)]
[PreserveSig]
int GetWindow(
[In] ref Guid rguidReason,
[In, Out] ref IntPtr phwnd);
[PreserveSig]
int OnSecurityProblem(
[In, MarshalAs(UnmanagedType.U4)] uint dwProblem);
}
public class MyWebBrowser : WebBrowser
{
public static Guid IID_IHttpSecurity
= new Guid("79eac9d7-bafa-11ce-8c82-00aa004ba90b");
public static Guid IID_IWindowForBindingUI
= new Guid("79eac9d5-bafa-11ce-8c82-00aa004ba90b");
public const int S_OK = 0;
public const int S_FALSE = 1;
public const int E_NOINTERFACE = unchecked((int)0x80004002);
public const int RPC_E_RETRY = unchecked((int)0x80010109);
protected override WebBrowserSiteBase CreateWebBrowserSiteBase()
{
return new MyWebBrowserSite(this);
}
class MyWebBrowserSite : WebBrowserSite,
UCOMIServiceProvider,
IHttpSecurity,
IWindowForBindingUI
{
private MyWebBrowser myWebBrowser;
public MyWebBrowserSite(MyWebBrowser myWebBrowser)
: base(myWebBrowser)
{
this.myWebBrowser = myWebBrowser;
}
public int QueryService(ref Guid guidService
, ref Guid riid
, out IntPtr ppvObject)
{
if (riid == IID_IHttpSecurity)
{
ppvObject = Marshal.GetComInterfaceForObject(this
, typeof(IHttpSecurity));
return S_OK;
}
if (riid == IID_IWindowForBindingUI)
{
ppvObject = Marshal.GetComInterfaceForObject(this
, typeof(IWindowForBindingUI));
return S_OK;
}
ppvObject = IntPtr.Zero;
return E_NOINTERFACE;
}
public int GetWindow(ref Guid rguidReason
, ref IntPtr phwnd)
{
if (rguidReason == IID_IHttpSecurity
|| rguidReason == IID_IWindowForBindingUI)
{
phwnd = myWebBrowser.Handle;
return S_OK;
}
else
{
phwnd = IntPtr.Zero;
return S_FALSE;
}
}
public int OnSecurityProblem(uint dwProblem)
{
//ignore errors
//undocumented return code, does not work on IE6
return S_OK;
}
}
}
}
I'm writing a program that needs to be able to extract the thumbnail image from a file. I've gotten a hold of a class, ThumbnailCreator, which is able to do this. The source of this Class is below.
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Text;
using System.IO;
using System.Drawing.Imaging;
internal class ThumbnailCreator : IDisposable
{
// Fields
private IMalloc alloc;
private Size desiredSize;
private bool disposed;
private static readonly string fileExtention = ".jpg";
private Bitmap thumbnail;
// Methods
public ThumbnailCreator()
{
this.desiredSize = new Size(100, 100);
}
public ThumbnailCreator(Size desiredSize)
{
this.desiredSize = new Size(100, 100);
this.DesiredSize = desiredSize;
}
public void Dispose()
{
if (!this.disposed)
{
if (this.alloc != null)
{
Marshal.ReleaseComObject(this.alloc);
}
this.alloc = null;
if (this.thumbnail != null)
{
this.thumbnail.Dispose();
}
this.disposed = true;
}
}
~ThumbnailCreator()
{
this.Dispose();
}
private bool getThumbNail(string file, IntPtr pidl, IShellFolder item)
{
bool CS;
IntPtr hBmp = IntPtr.Zero;
IExtractImage extractImage = null;
try
{
if (Path.GetFileName(PathFromPidl(pidl)).ToUpper().Equals(Path.GetFileName(file).ToUpper()))
{
int prgf;
IUnknown iunk = null;
Guid iidExtractImage = new Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1");
item.GetUIObjectOf(IntPtr.Zero, 1, ref pidl, ref iidExtractImage, out prgf, ref iunk);
extractImage = (IExtractImage) iunk;
if (extractImage != null)
{
SIZE sz = new SIZE {
cx = this.desiredSize.Width,
cy = this.desiredSize.Height
};
StringBuilder location = new StringBuilder(260, 260);
int priority = 0;
int requestedColourDepth = 0x20;
EIEIFLAG flags = EIEIFLAG.IEIFLAG_SCREEN | EIEIFLAG.IEIFLAG_ASPECT;
int uFlags = (int) flags;
extractImage.GetLocation(location, location.Capacity, ref priority, ref sz, requestedColourDepth, ref uFlags);
extractImage.Extract(out hBmp);
if (hBmp != IntPtr.Zero)
{
this.thumbnail = Image.FromHbitmap(hBmp);
}
Marshal.ReleaseComObject(extractImage);
extractImage = null;
}
return true;
}
CS = false;
}
catch (Exception)
{
if (hBmp != IntPtr.Zero)
{
UnManagedMethods.DeleteObject(hBmp);
}
if (extractImage != null)
{
Marshal.ReleaseComObject(extractImage);
}
throw;
}
return CS;
}
public Bitmap GetThumbNail(string file)
{
if (!File.Exists(file) && !Directory.Exists(file))
{
throw new FileNotFoundException(string.Format("The file '{0}' does not exist", file), file);
}
if (this.thumbnail != null)
{
this.thumbnail.Dispose();
this.thumbnail = null;
}
IShellFolder folder = getDesktopFolder;
if (folder != null)
{
IntPtr pidlMain;
try
{
int cParsed;
int pdwAttrib;
string filePath = Path.GetDirectoryName(file);
folder.ParseDisplayName(IntPtr.Zero, IntPtr.Zero, filePath, out cParsed, out pidlMain, out pdwAttrib);
}
catch (Exception)
{
Marshal.ReleaseComObject(folder);
throw;
}
if (pidlMain != IntPtr.Zero)
{
Guid iidShellFolder = new Guid("000214E6-0000-0000-C000-000000000046");
IShellFolder item = null;
try
{
folder.BindToObject(pidlMain, IntPtr.Zero, ref iidShellFolder, ref item);
}
catch (Exception)
{
Marshal.ReleaseComObject(folder);
this.Allocator.Free(pidlMain);
throw;
}
if (item != null)
{
IEnumIDList idEnum = null;
try
{
item.EnumObjects(IntPtr.Zero, ESHCONTF.SHCONTF_NONFOLDERS | ESHCONTF.SHCONTF_FOLDERS, ref idEnum);
}
catch (Exception)
{
Marshal.ReleaseComObject(folder);
this.Allocator.Free(pidlMain);
throw;
}
if (idEnum != null)
{
IntPtr pidl = IntPtr.Zero;
bool complete = false;
while (!complete)
{
int fetched;
if (idEnum.Next(1, ref pidl, out fetched) != 0)
{
pidl = IntPtr.Zero;
complete = true;
}
else if (this.getThumbNail(file, pidl, item))
{
complete = true;
}
if (pidl != IntPtr.Zero)
{
this.Allocator.Free(pidl);
}
}
Marshal.ReleaseComObject(idEnum);
}
Marshal.ReleaseComObject(item);
}
this.Allocator.Free(pidlMain);
}
Marshal.ReleaseComObject(folder);
}
return this.thumbnail;
}
private static string PathFromPidl(IntPtr pidl)
{
StringBuilder path = new StringBuilder(260, 260);
if (UnManagedMethods.SHGetPathFromIDList(pidl, path) != 0)
{
return path.ToString();
}
return string.Empty;
}
// Properties
private IMalloc Allocator
{
get
{
if (!this.disposed && (this.alloc == null))
{
UnManagedMethods.SHGetMalloc(out this.alloc);
}
return this.alloc;
}
}
public Size DesiredSize
{
get
{
return this.desiredSize;
}
set
{
this.desiredSize = value;
}
}
private static IShellFolder getDesktopFolder
{
get
{
IShellFolder ppshf;
UnManagedMethods.SHGetDesktopFolder(out ppshf);
return ppshf;
}
}
public Bitmap ThumbNail
{
get
{
return this.thumbnail;
}
}
// Nested Types
private enum EIEIFLAG
{
IEIFLAG_ASPECT = 4,
IEIFLAG_ASYNC = 1,
IEIFLAG_CACHE = 2,
IEIFLAG_GLEAM = 0x10,
IEIFLAG_NOBORDER = 0x100,
IEIFLAG_NOSTAMP = 0x80,
IEIFLAG_OFFLINE = 8,
IEIFLAG_ORIGSIZE = 0x40,
IEIFLAG_QUALITY = 0x200,
IEIFLAG_SCREEN = 0x20
}
[Flags]
private enum ESFGAO
{
SFGAO_CANCOPY = 1,
SFGAO_CANDELETE = 0x20,
SFGAO_CANLINK = 4,
SFGAO_CANMOVE = 2,
SFGAO_CANRENAME = 0x10,
SFGAO_CAPABILITYMASK = 0x177,
SFGAO_COMPRESSED = 0x4000000,
SFGAO_CONTENTSMASK = -2147483648,
SFGAO_DISPLAYATTRMASK = 0xf0000,
SFGAO_DROPTARGET = 0x100,
SFGAO_FILESYSANCESTOR = 0x10000000,
SFGAO_FILESYSTEM = 0x40000000,
SFGAO_FOLDER = 0x20000000,
SFGAO_GHOSTED = 0x80000,
SFGAO_HASPROPSHEET = 0x40,
SFGAO_HASSUBFOLDER = -2147483648,
SFGAO_LINK = 0x10000,
SFGAO_READONLY = 0x40000,
SFGAO_REMOVABLE = 0x2000000,
SFGAO_SHARE = 0x20000,
SFGAO_VALIDATE = 0x1000000
}
[Flags]
private enum ESHCONTF
{
SHCONTF_FOLDERS = 0x20,
SHCONTF_INCLUDEHIDDEN = 0x80,
SHCONTF_NONFOLDERS = 0x40
}
[Flags]
private enum ESHGDN
{
SHGDN_FORADDRESSBAR = 0x4000,
SHGDN_FORPARSING = 0x8000,
SHGDN_INFOLDER = 1,
SHGDN_NORMAL = 0
}
[Flags]
private enum ESTRRET
{
STRRET_WSTR,
STRRET_OFFSET,
STRRET_CSTR
}
[ComImport, Guid("000214F2-0000-0000-C000-000000000046"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
private interface IEnumIDList
{
[PreserveSig]
int Next(int celt, ref IntPtr rgelt, out int pceltFetched);
void Skip(int celt);
void Reset();
void Clone(ref ThumbnailCreator.IEnumIDList ppenum);
}
[ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("BB2E617C-0920-11d1-9A0B-00C04FC2D6C1")]
private interface IExtractImage
{
void GetLocation([Out, MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszPathBuffer, int cch, ref int pdwPriority, ref ThumbnailCreator.SIZE prgSize, int dwRecClrDepth, ref int pdwFlags);
void Extract(out IntPtr phBmpThumbnail);
}
[ComImport, Guid("00000002-0000-0000-C000-000000000046"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
private interface IMalloc
{
[PreserveSig]
IntPtr Alloc(int cb);
[PreserveSig]
IntPtr Realloc(IntPtr pv, int cb);
[PreserveSig]
void Free(IntPtr pv);
[PreserveSig]
int GetSize(IntPtr pv);
[PreserveSig]
int DidAlloc(IntPtr pv);
[PreserveSig]
void HeapMinimize();
}
[ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("000214E6-0000-0000-C000-000000000046")]
private interface IShellFolder
{
void ParseDisplayName(IntPtr hwndOwner, IntPtr pbcReserved, [MarshalAs(UnmanagedType.LPWStr)] string lpszDisplayName, out int pchEaten, out IntPtr ppidl, out int pdwAttributes);
void EnumObjects(IntPtr hwndOwner, [MarshalAs(UnmanagedType.U4)] ThumbnailCreator.ESHCONTF grfFlags, ref ThumbnailCreator.IEnumIDList ppenumIDList);
void BindToObject(IntPtr pidl, IntPtr pbcReserved, ref Guid riid, ref ThumbnailCreator.IShellFolder ppvOut);
void BindToStorage(IntPtr pidl, IntPtr pbcReserved, ref Guid riid, IntPtr ppvObj);
[PreserveSig]
int CompareIDs(IntPtr lParam, IntPtr pidl1, IntPtr pidl2);
void CreateViewObject(IntPtr hwndOwner, ref Guid riid, IntPtr ppvOut);
void GetAttributesOf(int cidl, IntPtr apidl, [MarshalAs(UnmanagedType.U4)] ref ThumbnailCreator.ESFGAO rgfInOut);
void GetUIObjectOf(IntPtr hwndOwner, int cidl, ref IntPtr apidl, ref Guid riid, out int prgfInOut, ref ThumbnailCreator.IUnknown ppvOut);
void GetDisplayNameOf(IntPtr pidl, [MarshalAs(UnmanagedType.U4)] ThumbnailCreator.ESHGDN uFlags, ref ThumbnailCreator.STRRET_CSTR lpName);
void SetNameOf(IntPtr hwndOwner, IntPtr pidl, [MarshalAs(UnmanagedType.LPWStr)] string lpszName, [MarshalAs(UnmanagedType.U4)] ThumbnailCreator.ESHCONTF uFlags, ref IntPtr ppidlOut);
}
[ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("00000000-0000-0000-C000-000000000046")]
private interface IUnknown
{
[PreserveSig]
IntPtr QueryInterface(ref Guid riid, out IntPtr pVoid);
[PreserveSig]
IntPtr AddRef();
[PreserveSig]
IntPtr Release();
}
[StructLayout(LayoutKind.Sequential)]
private struct SIZE
{
public int cx;
public int cy;
}
[StructLayout(LayoutKind.Explicit, CharSet=CharSet.Auto)]
private struct STRRET_ANY
{
// Fields
[FieldOffset(4)]
public IntPtr pOLEString;
[FieldOffset(0)]
public ThumbnailCreator.ESTRRET uType;
}
[StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto, Pack=4)]
private struct STRRET_CSTR
{
public ThumbnailCreator.ESTRRET uType;
[MarshalAs(UnmanagedType.ByValArray, SizeConst=520)]
public byte[] cStr;
}
private class UnManagedMethods
{
// Methods
[DllImport("gdi32", CharSet=CharSet.Auto)]
internal static extern int DeleteObject(IntPtr hObject);
[DllImport("shell32", CharSet=CharSet.Auto)]
internal static extern int SHGetDesktopFolder(out ThumbnailCreator.IShellFolder ppshf);
[DllImport("shell32", CharSet=CharSet.Auto)]
internal static extern int SHGetMalloc(out ThumbnailCreator.IMalloc ppMalloc);
[DllImport("shell32", CharSet=CharSet.Auto)]
internal static extern int SHGetPathFromIDList(IntPtr pidl, StringBuilder pszPath);
}
}
As a test I created a quick console application, the code of which is below. This test worked fine and was able to extract a thumbnail, and saved it to a PNG file.
static void Main(string[] args)
{
try
{
Console.WriteLine("press a key to extract");
System.Console.ReadKey();
string path = #"C:\somefile.xyz";
ThumbnailCreator creator = new ThumbnailCreator();
creator.DesiredSize = new Size(600, 600);
Bitmap bm = creator.GetThumbNail(path);
bm.Save(#"C:\blah.png", System.Drawing.Imaging.ImageFormat.Png);
Console.WriteLine("press a key to exit");
System.Console.ReadKey();
}
catch (Exception exp)
{
Console.WriteLine(exp.Message);
}
}
My problem is the real application I want to use this in runs as a plug-in for another application. When I try to run the same test code in the plug-in creator.GetThumbNail(path); returns null.
I debugged a little further and found that in the method ThumbnailCreator.getThumbNail(string file, IntPtr pidl,IshellFolder item) the line extractImage.Extract(out hBmp); returns IntPtr.Zero. Whereas in the console application that works this method actually returns a number. Maybe this is the problem? Or maybe this problem happens before this. Honestly, I'm completely lost when it comes to Interop and Windows API stuff.
Does anyone know of any possible reasons why this class would work in a standalone console application, but not as part of a plug-in for another application?
Update
Here's a bit more detail of how this plug-in is created. To add a custom command to this program you create a class that implements an ICommand interface from is API. The interface has a single Execute() method where code is place that should run when the user executes the custom command from the program. The native application, however, is what actualy instantiates my command class and calls the execute method.
What could be different about the way that the native app instantiates my command class and or calls the Execute() method that would prevent the thumbnail extraction from working?
Just ran across this issue myself and I do say, it took some time to figure out that it was a bitness issue. In your scenario your console app was probably compiled as x64 and your Windows app as x86.
The ExtractImage interface (BB2E617C-0920-11d1-9A0B-00C04FC2D6C1) on a 64bit OS is only accessible from 64bit applications (because explorer is 64bit), thus resulting in a "Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG))" exception in applications compiled as x86.
Code that calls the Shell API must be in a COM Single Threaded Apartment, try putting [STAThread] attribute on the thread that calls this.