CodeProject: Working With Microsoft.mshtml.dll and SHDocVw.dll. Free source code and programming help

I was working On BHO for IE in C#. Initially I was not knowing any thing about BHO and IE extentions. I read articles and Architecture and related information from MSDN. Also I read Architecture of IE on MSDN.

But I got the best understanding of BHO onCode Project By Pavel Zolnikov. I have listed some problem that i had faced and Solution of those problem.

Microsoft.mshtml.dll and SHDocVW.dll

I was working On BHO TOOL BAR. I was trying to access Object element (<object> Tag), Image Element(<img> Tag), Embed Element (<embed> Tag). I had initially problem that how to get this element.

I was using Both of them, because in many case 2nd approach is failed to detect the Object Tag.

Injection Javascript in any Web Pages

Handling Web Document Events

Now there was a Problem with this method...After Implementing above way of code...it was stop the actual events of the browser. Means No events on web Browser was fired. In Other words Events of Web Browser was Locked. So it was a little and annoying problem, but I found solution for this problem Here By Rick Strahl

Collecting All the Images From Web Page

I was trying to access All the images from the Web Page. It can be done one of the following way.

By Document.Images Collection

By getElementsByTagName

Accessing Content From Frames and IFrames

The Biggest problem was to access content from frames and Iframes. I had tried lot to access content from Frame and Iframe. But it was giving me always IFrameElement or Access Denied Exception.

Using Above CodeI was able to access the frame but it was giving Access Denied Exception. I was also trying to attach event with Frame/Iframe Document but there was same problem. Finally I got the solution from HERE. I done as follows:

Get all the Attributes of the Tag / Element

I was required to get all the attributes of the tag. Attributes like height , width, src etc. I was able to get all the attribute as follows.

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How to automatically click on alert confirm box ?

binhvtt

19:38 13 Oct '09

Hi I have a question that how to automatically click on OK button in alert confirm dialog of javascript?
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My vote of 1

Member 1328610

4:39 23 Jul '09

Poor English and content.
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get IE menubar, toolbar click notifications

sumedh.shrikrushana

1:03 16 Jul '09

Hi All, i am working on project which requires logging user action on internet explorer. I am able to get browsing event using BHO, but not able to log menu bar, toolbar events. your valuable comments required. Please help me!! thanks.
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Re: get IE menubar, toolbar click notifications

EmersioN

2:22 16 Jul '09

Dear Sumedh, BHO provides event related to browser... and menu and tool bar are not part of browser... and even development of toolbar needs BHO.. EmersioN
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Re: get IE menubar, toolbar click notifications

sumedh.shrikrushana

19:49 16 Jul '09

Hi EmersioN, thanks for the comments, can u provide some information/links about different ways for getting toolbar/menubar events.
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Re: get IE menubar, toolbar click notifications

EmersioN

21:13 16 Jul '09

Hi, You can write Mouse hooks and on mouse events you can find active element by mouse position and you can have event details as well.. if control beneath is in tool bar then you can record it otherwise ignore it... this is very typical way and hooks can crash your browser so becareful.. EmersioN
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Transform mshtml.HtmlImgClass to bytes or File Or Image etc

llpnet

12:00 27 Jan '09

any way? Saludos, Luis Alfredo Lozada Portal Microsoft DCE3 Trujillo - Perú
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Re: Transform mshtml.HtmlImgClass to bytes or File Or Image etc

EmersioN

18:20 27 Jan '09

Actually No... mshtml.HtmlImgClass gives you a HTML element IMG. Now form SRC attribute of IMG u can open stream and may get bytes of Image !!! EmersioN
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How to Access the Contents/tags of iframe in BHO

harshkapoors

5:36 20 Jan '09

Hi,

I have read this page and impllemented the functionality but i couldn't got the right solution. i think i couldn't implemented it in right place.

Actually i am working with BHO, that works to get the URL of the site and access the contents/tags of iframe and for this i register it firstly.

public void OnDocumentComplete(object pDisp, ref object URL)
{
foreach (HTMLIFrame tempElement in document.getElementsByTagName ("iframe"))
{
System.Windows.Forms.MessageBox.Show(URL.ToString());
}
}

public int SetSite(object site)
{

if (site != null)
{
webBrowser = (WebBrowser)site;
webBrowser.DocumentComplete += new DWebBrowserEvents2_DocumentCompleteEventHandler(this.OnDocumentComplete);
}
else
{
webBrowser.DocumentComplete +=new DWebBrowserEvents2_DocumentCompleteEventHandler(this.OnDocumentComplete);
webBrowser = null;
}
return 0;
}

from this i am fetching the URL of the iframe but how can i access the tags of iframe?

and where i have to implement it?

Please give me a solution.

Thanx in advance.

Regards
Harsh

Re: How to Access the Contents/tags of iframe in BHO

EmersioN

19:20 20 Jan '09

Hi harsh...
do not use set site.. here is small snippet which will help you....

[Guid("Guid-Guid-Guid-Guid-Guid")]
    [BandObject("ToolBar", BandObjectStyle.Horizontal | BandObjectStyle.ExplorerToolbar, HelpText = "ToolBar")]
    [ComVisible(true), ClassInterface(ClassInterfaceType.None)]
    public partial class ToolBar : BandObject
    {
public void ToolBar()

{
         this.Load += new EventHandler(ToolBar_Load);

} //end of constructor

 
        void ToolBar_Load(object sender, EventArgs e)
        {
            try
            {
              this.Explorer.DownloadComplete += new DWebBrowserEvents2_DownloadCompleteEventHandler(Explorer_DownloadComplete);
//you can also use Explorer_DocumentComplete event 
             }catch(){//handle ex here}
}//end if Load function

   void Explorer_DownloadComplete()
        {
            try
            {
                IHTMLElementCollection elcol = htmlDoc.getElementsByTagName("iframe");
                foreach (IHTMLElement iel in elcol)
                {
                    HTMLFrameElement frm = (HTMLFrameElement)iel;

                    DispHTMLDocument doc = (DispHTMLDocument)((SHDocVw.IWebBrowser2)frm).Document;
                    MessageBox.Show(doc.body.innerHTML); //do your processing here...
                 } 
               
             }catch(){//handle ex here}
        }//end of  Explorer_DownloadComplete

}//end of class

Happy Coding...
Cool

EmersioN

Re: How to Access the Contents/tags of iframe in BHO

harshkapoors

2:56 21 Jan '09

Hi Emersion,

Here(below) is my complete code for getting an URL , and as you know that my next target to read the tags of iframe. and code mentioned by you is only to fetch the tags of iframe.

i have used this code but didnt get ant solution.

.........................................................................

IHTMLElementCollection elcol = htmlDoc.getElementsByTagName("iframe");
foreach (IHTMLElement iel in elcol)
{
HTMLFrameElement frm = (HTMLFrameElement)iel;
DispHTMLDocument doc = (DispHTMLDocument)((SHDocVw.IWebBrowser2)frm).Document;
System.Windows.Forms.MessageBox.Show(doc.body.innerHTML); //do your processing here...
}
.........................................................................

and one thing more please describe me about BandObject class? and htmldoc object of which class? i think HtmlDocument, but will we assign any value in it before?

will you please mention that where i have to use your given code?

public void OnDocumentComplete(object pDisp, ref object URL)
{
foreach (HTMLIFrame tempElement in document.getElementsByTagName ("iframe"))
{
System.Windows.Forms.MessageBox.Show(URL.ToString());
}
}

public int SetSite(object site)
{

if (site != null)
{
webBrowser = (WebBrowser)site;
webBrowser.DocumentComplete += new DWebBrowserEvents2_DocumentCompleteEventHandler(this.OnDocumentComplete);
}
else
{
webBrowser.DocumentComplete +=new DWebBrowserEvents2_DocumentCompleteEventHandler(this.OnDocumentComplete);
webBrowser = null;
}
return 0;
}

public int GetSite(ref Guid guid, out IntPtr ppvSite)
{
IntPtr punk = Marshal.GetIUnknownForObject(webBrowser);
int hr = Marshal.QueryInterface(punk, ref guid, out ppvSite);
Marshal.Release(punk);
return hr;

}

public static string BHOKEYNAME = "Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Browser Helper Objects";

[ComRegisterFunction]
public static void RegisterBHO(Type type)
{
RegistryKey registryKey = Registry.LocalMachine.OpenSubKey(BHOKEYNAME, true);

if (registryKey == null)
registryKey = Registry.LocalMachine.CreateSubKey(BHOKEYNAME);

string guid = type.GUID.ToString("B");
RegistryKey ourKey = registryKey.OpenSubKey(guid);

if (ourKey == null)
ourKey = registryKey.CreateSubKey(guid);

ourKey.SetValue("Alright", 1);
registryKey.Close();
ourKey.Close();
}

[ComUnregisterFunction]
public static void UnregisterBHO(Type type)
{
RegistryKey registryKey = Registry.LocalMachine.OpenSubKey(BHOKEYNAME, true);
string guid = type.GUID.ToString("B");

if (registryKey != null)
registryKey.DeleteSubKey(guid, false);
}

}

Thanks in advance

Harsh.

Re: How to Access the Contents/tags of iframe in BHO

EmersioN

18:14 21 Jan '09

Hi , Harsh

please read article by Pavel Zolnikov
[^] on code project.
this is nice article to understand BHO..
And the code i had posted..it is inheriting class from code of Pavel Zolnikov.
He has done almost all things for us..including getSite and SetSite.
And for rest of the the classes you must refer MSDN.

And final answer where to write a code?
I had mentioned it in last answer to you...
please refer that code again..
I have written a complete class demo that is inherited from BHo (of Pavel Zolnikov).
and then Constructor, Load event of class and Document event as well.

HAppy Coding...
Smile

EmersioN

Re: How to Access the Contents/tags of iframe in BHO

harshkapoors

5:26 22 Jan '09

Hi Dear, Still not working, my dll is not being register. Provide me the solution. Harsh
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Re: How to Access the Contents/tags of iframe in BHO

EmersioN

18:34 22 Jan '09

can u give exact error/problem situation for this ?? EmersioN
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Re: How to Access the Contents/tags of iframe in BHO

harshkapoors

20:57 22 Jan '09

Hi,

I have gone through the BandObject class, i found many things that are not useful for me , so i retrieved onle GetSite, SetSite function that i have already implemented and the remaining part u have given to me. i am using two functions fro registered and unregistered the dll from GAC.
now dll not being registered.

"RegAsm : warning RA0000: Registering an unsigned assembly with /codebase can use your assembly to interface with other application that may be installed on the same computer."

something like this - this prob occured when we dont use public access modifier. but i am using public class ToolBar but sprob still remain same.

Waiting for ur reply

Harsh

Re: How to Access the Contents/tags of iframe in BHO

harshkapoors

4:10 23 Jan '09

Hi,

here is my complete code, still it is not finding the tags of iframe.
-------------------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using mshtml;
using System.Web;
using SHDocVw;
using System.Diagnostics;
using Microsoft.Win32;

namespace BHO_HelloWorld
{

public class ToolBar : IObjectWithSite
{
SHDocVw.WebBrowser webBrowser;
SHDocVw.WebBrowserClass Explorer = new WebBrowserClass();
public void ToolBar()
{

}

public void Explorer_DownloadComplete(object pDisp, ref object URL)
{
try
{
System.Windows.Forms.MessageBox.Show(URL.ToString());
HTMLDocument htmlDoc = (HTMLDocument)this.Explorer.IWebBrowser_Document;
IHTMLElementCollection elcol = htmlDoc.getElementsByTagName("iframe");
foreach (IHTMLElement iel in elcol)
{
HTMLFrameElement frm = (HTMLFrameElement)iel;
DispHTMLDocument doc = (DispHTMLDocument)((SHDocVw.IWebBrowser2)frm).Document;
System.Windows.Forms.MessageBox.Show(doc.body.innerHTML); //do your processing here...
}
}
catch
{//handle ex here
}
}//end of Explorer_DownloadComplete

public int SetSite(object site)
{

if (site != null)
{
//System.Windows.Forms.MessageBox.Show("Harsh Kapoor");
webBrowser = (WebBrowser)site;
webBrowser.DocumentComplete += new DWebBrowserEvents2_DocumentCompleteEventHandler(this.Explorer_DownloadComplete);
}
else
{
// System.Windows.Forms.MessageBox.Show("HarshKapoor");
webBrowser.DocumentComplete += new DWebBrowserEvents2_DocumentCompleteEventHandler(this.Explorer_DownloadComplete);
webBrowser = null;
}
return 0;
}

public int GetSite(ref Guid guid, out IntPtr ppvSite)
{
IntPtr punk = Marshal.GetIUnknownForObject(webBrowser);
int hr = Marshal.QueryInterface(punk, ref guid, out ppvSite);
Marshal.Release(punk);
return hr;

}

public static string BHOKEYNAME = "Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Browser Helper Objects";

[ComRegisterFunction]
public static void RegisterBHO(Type type)
{
RegistryKey registryKey = Registry.LocalMachine.OpenSubKey(BHOKEYNAME, true);

if (registryKey == null)
registryKey = Registry.LocalMachine.CreateSubKey(BHOKEYNAME);

string guid = type.GUID.ToString("B");
RegistryKey ourKey = registryKey.OpenSubKey(guid);

if (ourKey == null)
ourKey = registryKey.CreateSubKey(guid);

ourKey.SetValue("Alright", 1);
registryKey.Close();
ourKey.Close();
}

[ComUnregisterFunction]
public static void UnregisterBHO(Type type)
{
RegistryKey registryKey = Registry.LocalMachine.OpenSubKey(BHOKEYNAME, true);
string guid = type.GUID.ToString("B");

if (registryKey != null)
registryKey.DeleteSubKey(guid, false);
}

}//end of class

}

Re: How to Access the Contents/tags of iframe in BHO [modified]

EmersioN

18:31 26 Jan '09

Hello Harsh... Sorry for late reply.. I would like to suggest you...to inherit your tool bar...from Pavel Zolnikov's Class.[^] He has done most of the things and in Exact manner. please try to use it or Study it completely if you want to write your own. Happy Coding !! modified on Tuesday, January 27, 2009 11:20 PM
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where to add

tsahiB

6:02 17 Jan '09

i'm a noob to C# so sorry for the question

I'm using Pavel Zolnikov example.
i've created a new class which inherit from HelloWorldBar
there I have a function called ExplorerOnDocumentComplete. there I want to handle all the events. inside it i've entered your code

this is Pavel SetSite (the last line is mine)


.
.
try
{
object w;
sp.QueryService( 
ref guid,
ref riid,
out w );
Explorer = (WebBrowserClass)Marshal.CreateWrapperOfType(
						w as IWebBrowser,
						typeof(WebBrowserClass)
						);                 
OnExplorerAttached(EventArgs.Empty);
// I added this
Explorer.DocumentComplete += new DWebBrowserEvents2_DocumentCompleteEventHandler(ExplorerOnDocumentComplete);

does it should work that way?
as my understanding if I want to rehook my events all the time then all the code (all the events I want to catch) should be inside my function, right?

Re: where to add

EmersioN

18:20 18 Jan '09

you should have code as like follows...

    
    [Guid("AE07141B-45D4-4a98-5F68-0333EA26E115")] //your GUID goes here
    [BandObject("YourNewChildClass", BandObjectStyle.Horizontal | BandObjectStyle.ExplorerToolbar, HelpText = "YourNewChildClass")]
    [ComVisible(true), ClassInterface(ClassInterfaceType.None)]
    public partial class YourNewChildClass: BandObject//Class from Pavel Zolnikov example
    {

         .
         .
         . //declaration and other functions e.g constructor etc
         .

 void YourNewChildClass_Load(object sender, EventArgs e) //load function of your class ..this is similar to Form Load event
   {
   try
   {
   this.Explorer.DownloadComplete += new DWebBrowserEvents2_DownloadCompleteEventHandler(Explorer_DownloadComplete);
                   
   }
   catch (Exception ex)
   {
   //Something was wrong
                MessageBox.Show(ex.Message);
   }
   } //end of Load function..


}//end of YourNewChildClass

Happy Coding
Smile

EmersioN

Re: where to add

tsahiB

10:56 14 Feb '09

first of all, thanks EmersioN for your help
I have 3 questions:
1. in the Mouse_Down event the browser stops after the messagebox. meaning when I'm clicking on a link(in explorer) i'm getting the messagebox
but the browser doesnt redirect me to the page. what should I do?
2. how do I know which element fired the event? (button,checkbox, textbox, plain text)?
3. when i'm debugging ( by clicking F5 i'm getting an error "Error while trying to run the project: Unable to start debugging". do you
know why i'm getting this ? (debuuging is working when i'm using "attach to process" )

thanks

Re: where to add

EmersioN

18:38 15 Feb '09

Hello dear for this problem please read Article's "Handling Web Document Events" and for more detail... Web Document Events[^] Keep Coding.... EmersioN
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Re: where to add

tsahiB

11:00 19 Feb '09

ok, thanks the post helped me but still dont know how to tell which element fired the event do I need to use the e.srcElement.innerHTML to know? or there is a better way ?
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Re: where to add

EmersioN

19:39 19 Feb '09

as i mentioned in first reply you can add html document completed (or load) event handler in load event of tool bar. and in html document completed(or load) event you can find element by id or name and can event handler for it. EmersioN
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Explorer.IWebBrowser_Document is null

Maverickcool

11:27 4 Jan '09

for some reason this property is null what do I need to do to initialize it? I added: WebBrowserClass Explorer = new WebBrowserClass();
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Re: Explorer.IWebBrowser_Document is null

EmersioN

18:39 4 Jan '09

Hi.. can you give exact piece of code and situation where this is occurring ?? do you mean `this.Explorer` is null ?? please do provide some sort of your code. EmersioN
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Last Visit: 6:13 22 Nov '09 Last Update: 6:13 22 Nov '09

12 Next »

Introduction

Background

Microsoft.mshtml.dll and SHDocVW.dll

Injection Javascript in any Web Pages

Handling Web Document Events

Collecting All the Images From Web Page

By Document.Images Collection

By getElementsByTagName

Accessing Content From Frames and IFrames

Get all the Attributes of the Tag / Element