Need help with interface pointer.

[Elias Montoya]

Im not very used to this new way to use OCX controls in PB10.

When i get a pointer to an interface, and try to use it, i get a compile time error. For example:

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Local iDpx     As IDispatch
Local Selection   As IHTMLDocument2

iDpx = DHTMLEdit(Onum).dom
           
Selection = iDpx.get_selection  '<------ Compile time error

What i am aiming to is to use PasteHTML method on the DHTMLEdit control. Im sure im doing something wrong. Any hints?

[José Roca]

You're dimming iDpx as IDispatch. Therefore, you only can call the 4 methods of the IDispatch interface and the 3 methods of the IUnknown interface with it. You have to dim iDpx as the inerface that implements the get_Selection method that you intend to call.

[Elias Montoya]

Thanks for the reply Jose. Your reply makes sense to me, and I also tried that before.
the reason i tried the code i posted above was because I was getting the same results,
and i wanted to try something else.

Here's the code i used first:

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Local iDpx     As IHTMLDocument2
Local Selection   As IHTMLSelectionObject

iDpx = DHTMLEdit(Onum).dom  '<--- get the pointer to the dispatch interface 'IHTMLDocument2'
           
Selection = iDpx.get_selection  '<------ Compile time error

Also tried:

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Call iDpx.get_selection to Selection

But no luck.... 

[José Roca]

If you're using my headers for MSHTML, there is not a get_selection method, but a selection property. Therefore, use Selection = iDpx.selection

[Elias Montoya]

Right. That works. But i am using this headers:

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########################################################################################
' Library name: MSHTML
' Version: 4.0, Locale ID = 0
' Description: Microsoft HTML Object Library
' Path: C:\Windows\System32\mshtml.tlb
' Library GUID: {3050F1C5-98B5-11CF-BB82-00AA00BDCE0B}
' Code generated by the TypeLib Browser 5.0.0 (c) 2011 by Jose Roca
' Date: 11 ene 2012   Time: 17:29:39
' Options used to generate the code:
' - Add prefix in parameter names
' ########################################################################################

And i see this method in the interface i added to my code:

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########################################################################################
' Interface name = IHTMLDocument2
' IID = {332C4425-26CB-11D0-B483-00C04FD90119}
' Attributes = 4160 [&H00001040] [Dual] [Dispatchable]
' Inherited interface = IHTMLDocument
' ########################################################################################

#If Not %DEF(%IHTMLDocument2_INTERFACE_DEFINED)
    %IHTMLDocument2_INTERFACE_DEFINED = 1

Interface IHTMLDocument2 $IID_IHTMLDocument2

   Inherit IDispatch

  [REMOVED MANYE METHODS TO SHORTEN POST SIZE]

   ' =====================================================================================
   Method get_selection ( _                             ' VTable offset = 84
   ) As IHTMLSelectionObject                            ' [retval][out] **p IHTMLSelectionObject <dispinterface>
   ' =====================================================================================
   Method get_readyState ( _                            ' VTable offset = 88
   ) As wString                                         ' [retval][out] *p VT_BSTR
   ' =====================================================================================
   Method get_frames ( _                                ' VTable offset = 92
   ) As IHTMLFramesCollection2                          ' [retval][out] **p IHTMLFramesCollection2 <dispinterface>
   ' =====================================================================================
   Method get_embeds ( _                                ' VTable offset = 96
   ) As IHTMLElementCollection                          ' [retval][out] **p IHTMLElementCollection <dispinterface>
   ' =====================================================================================
   Method get_plugins ( _                               ' VTable offset = 100
   ) As IHTMLElementCollection                          ' [retval][out] **p IHTMLElementCollection <dispinterface>
   ' =====================================================================================
   Method put_alinkColor ( _                            ' VTable offset = 104
     ByVal Variant _                                    ' [in] p VT_VARIANT <Variant>
   )                                                    ' void

  [REMOVED MANY METHODS TO SHORTEN POST SIZE]

End Interface

#EndIf   ' /* __IHTMLDocument2_INTERFACE_DEFINED__ */

My guess is that the interface is being defined somewhere before in your headers... and the:

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#If Not %DEF(%IHTMLDocument2_INTERFACE_DEFINED)

Is jumping over the ones i added. I got these from your typelib browser, so, most likely that is the problem.
I will take a look at your interface definitions and use those instead.

Thanks Jose.

[José Roca]

You get these if the option "Use METHOD and PROPERTY/GET statements" is unchecked; otherwise, you get the already defined ones in my headers. My headers have interface definitions for all the Windows COM subsystem, so better leave the browser for third-party COM servers.

[Elias Montoya]

That explains it all. And now everything is working as it should. Thanks Jose.

[Elias Montoya]

 Again interface pointers, Things like these are the ones that puzzles me.

I DO see the script property. I can't access it. Even if i add my own interface definition, using an extravagant name that i cannot make errors with, it would not allow me to access the Script property.

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FUNCTION GetDesignerCode(OCXControl As Long) As String

Local WB    As IWebBrowser2
Local Doc   As IHTMLDocument
Local wStr  As wString
   
WB = OC_GetDispatch(OCXControl)

If IsObject(WB) Then   
   Doc = WB.Document
                                   
   wStr = Doc.Script   '<---- compile time error
                                 
   FUNCTION = wStr
End If   

End FUNCTION


I saw that the 'Script' Property is also 'inherited' in IHTMLDocument2 (although i didnt see the inherit part), but defining Doc, as IHTMLDocument2, would not help either. Now what am i doing wrong?? 

[José Roca]

You can't change interface definitions at your will and expect to work. The script property of the IHtmlDocument interface returns an IDispatch pointer to the script engine, not a string with the text of the script as you seem to want.

IHTMLDocument::Script Property

Gets an interface pointer that provides access to the scripting object via a handle to the script engine.

Syntax

    HRESULT IHTMLDocument::get_Script(IDispatch **p);

Parameters

    p
        Address of a pointer to a variable of type IDispatch interface that receives a handle to the script engine.

Return Value

    Returns S_OK if successful, or an error value otherwise.

What to do with this pointer is something that I haven't yet explored.

[Elias Montoya]

 You are right.

I was being deceived by the error that i was receiving:

METHOD OR PROPERTY NAME EXPECTED.

I thought it was refering to the method or property name i was using with the interface, and not the variable name where i was trying to store the result. No wonder why it wasn't working.

I guess it would be clearer to say:

IDISATCH VARIABLE EXPECTED.

or

DATA TYPE MISMATCH.