Accessing Internet Explorer instance parentWindow

nzakas · February 16th, 2006, 10:57 PM

Hi all,

I'm trying to get access to the execScript() method of a running Internet Explorer instance using C#. I have run aximp on SHDocVw.dll and use both it and mshtml as references in the project. I am able to get an instance of IE and then an instance of the HTMLDocument object, but when I try to access parentWindow, I get this error:

Code:

System.Runtime.InteropServices.COMException (0x80040154): Class not registered
   at System.RuntimeType.ForwardCallToInvokeMember(String memberName, BindingFlags flags, Object target, Int32[] aWrapperTypes, MessageData& msgData)
   at mshtml.HTMLDocumentClass.get_parentWindow()
   at TestIEApp.Class1.Main(String[] args) in e:\visual studio projects\testieapp\class1.cs:line 31

The code I use looks like this:

Code:

using System;
using mshtml;
using SHDocVw;

namespace TestIEApp
{
    /// <summary>
    /// Summary description for Class1.
    /// </summary>
    class Class1
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main(string[] args)
        {
            ShellWindowsClass sws = new ShellWindowsClass();

            System.Console.WriteLine("There are {0} instances of IE running.", sws.Count);

            foreach(InternetExplorer ie in sws) 
            {
                try 
                {
                    HTMLDocument doc = (HTMLDocument) ie.Document;
                    System.Console.WriteLine("IE Instance: " + doc.title);

                    try 
                    {                        
                        doc.parentWindow.alert("hi");
                    } 
                    catch (Exception ex) 
                    {
                        System.Console.WriteLine(ex.ToString());
                    }
                } 
                catch (Exception ex) 
                {
                    System.Console.WriteLine("Not IE");
                }
            }

            System.Console.ReadLine();
        }
    }
}

Does anyone have any idea why this happening and how I can workaround it?

Thanks.

Nicholas C. Zakas
Author, Professional JavaScript for Web Developers (ISBN 0764579088)
http://www.nczonline.net/