AxWebBrowser problems in VS2005

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Guest

It appears that I cannot correctly install the AxWebBrowser in VS2005.

I can instantiate an "AxWebBrowser browser" and refer to its members,
properties, and methods. I'm having trouble with the AxWebBrowser.Document:
When I print browser.Document.GetType().ToString() at runtime, I get
"mshtml.HTMLDocumentClass". But The VS2005 compiler does not recognize the
member AxWebBrowser.Document as anything other than a System.Object -- e.g.,
"Define doc As mshtml.HTMLDocumentClass = browser.Document" will fail to
compile with "Type 'mshtml.HTMLDocumentClass' is not defined."

When I try to install the missing component(s) via "aximp" and "tlbimp",
there seems to be no effect whatsoever. The commands I run in the project
directory, in a VS.NET Command Prompt, are:

aximp c:\windows\system32\shdocvw.dll
tlbimp mshtml.tlb

The only suspicious behavior that goes on during the installation itself is
a short list of warnings generated by tlbimp. They are as follows:

TlbImp : warning TI0000 : At least one of the arguments for
'IActiveIMMApp.GetDe faultIMEWnd' cannot be marshaled by the runtime
marshaler. Such arguments will therefore be passed as a pointer and may
require unsafe code to manipulate.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '__MIDL___MIDL_itf_mshtml_0256_0010.hbmpChecked'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '__MIDL___MIDL_itf_mshtml_0256_0010.hbmpUnchecked'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '__MIDL___MIDL_itf_mshtml_0256_0010.hbmpItem'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '_userBITMAP.pBuffer'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '__MIDL___MIDL_itf_mshtml_0256_0011.hbmpChecked'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '__MIDL___MIDL_itf_mshtml_0256_0011.hbmpUnchecked'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '__MIDL___MIDL_itf_mshtml_0256_0011.hbmpItem'.
TlbImp : warning TI0000 : The type library importer could not convert the
signat ure for the member '_FLAGGED_BYTE_BLOB.abData'.
Type library imported to MSHTML.dll

Whether or not these warnings are significant enough to prevent proper
installation, I do not know. In any event, the control doesn't seem to be
getting installed correctly at all. Any advice on doing this correctly or
determing the point of failure of this component's installation in the dev
environment?

--------

Bonus points: I am afraid I'm missing the bigger picture with typecasting in
VB .NET 2.0. Even though the compiler thinks AxWebBrowser.Document is a
simple Object, it still lets me reference members within it that only exist
in mshtml.HTMLDocumentClass. That is, it doesn't complain that System.Object
has no such member as "documentelement". In fact, I've even tried nonsense
strings like "foobar" -- anything goes! The compiler will allow me to
pretend that AxWebBrowser.Document has any imaginary members I want it to
have, and then waits until runtime to see if I'm right. If the member does
exist, then great, the runtime environment hands it to me as a plain
System.Object. (From there, I can even continue printing out
GetType().ToString(). In this manner I've learned of the existence of a
whole slew of classes I should have but don't have, such as
mshtml.HTMLHtmlElementClass.) Otherwise -- that is, if the member doesn't
exist ("foobar" or what have you) -- it hangs forever trying to search for
it. My questions are:
1) Why is the compiler so relaxed about missing datatypes, coercing them
upwards into Objects instead of complaining that they're missing?
2) Why does the compiler get so lenient about nonexistent members whenever
this happens?
3) Why does VB .NET hang whenever it can't find something, rather than
gracefully reporting the problem (e.g., by throwing an exception)?
 
I'm trying to use the AxWebBrowser. As far as I can tell the .NET 2.0
WebBrowser doesn't expose all of the functionality I need.
 
Dave,

I and probably me not alone (and seeing people strugling with that) did
never succeed in direct instancing the AxWebbrowser. Did you already drag an
webbrowser on a form from the toolbox?

Cor
 
Hi Dave,

Thank you for posting.

The Documnent property of the AxWebBrowser is Object typed and read-only.
There's a Navigate() method in the AxWebBrowser class which could be used
to display a url resource such as a html page, a jpg file, a word document
and so on. Then at run-time, we could use the Document property of the
AxWebBrowser to get an object representing the resource currently displayed
in the AxWebBrowser control. The type of the Document varies with the type
of the resource which the AxWebBrowser is browsing. For example, if the
resource is a html page, the type of the Document will be
"mshtml.HTMLDocumentClass". And if the resource is a word document, the
type of the Document will be "Microsoft.Office.Interop.Word.DocumentClass".
That is to say, the compiler could not determine which type the Document is
at design-time.

Because the resource is accessed and displayed at run-time, the compiler
could not check out any error when compiling even if the resource doesn't
exist. When running, a default web page saying "The page cannot be
displayed" will appear in the AxWebBrowser control if the resource doesn't
exist and it doesn't take a long time to display this default web page. I
have performed a test and confirmed this.

Hope this is helpful to you.
If you have any concerns or need anything else, please don't hesitate to
let me know.


Sincerely,
Linda Liu
Microsoft Online Community Support

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Dave Booker said:
I'm trying to use the AxWebBrowser. As far as I can tell the .NET 2.0
WebBrowser doesn't expose all of the functionality I need.
Click to expand...

Which functionality do you need? Note that
'WebBrowser1.Document.DomDocument' provides access to the unmanaged document
object.
 
Hi Dave,

You have mentioned that "Define doc As mshtml.HTMLDocumentClass =
browser.Document" will fail to compile with "Type
'mshtml.HTMLDocumentClass' is not defined."

The type HTMLDocumentClass is located in Microsoft.mshtml assembly and the
namespace is mshtml. To use the type HTMLDocumentClass in your code, you
should add a reference to Microsoft.mshtml into your project.

Hope this is helpful to you.
If you have any other concerns or need anything else, please don't hesitate
to let me know.


Sincerely,
Linda Liu
Microsoft Online Community Support

====================================================
When responding to posts,please "Reply to Group" via
your newsreader so that others may learn and benefit
from your issue.
====================================================
 
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