Interop - Marshaling Arrays From .NET To COM Object?
May 25, 2009
I have a VB6 program which calls a COM method, passing 2 arrays as parameters and expecting 2 arrays to be populated in response.The code is this, where ItemIDs and ItemClientHandles are the input array parameters and MyItemServerHandles and Errors are populated by the COM object.
Dim ItemIDs(2) As String
Dim ItemClientHandles(2) As Long
Dim Errors() As Long ' Array for returned Item related errors
Dim MyItemServerHandles() As Long ' Server Handles for Items
I've found a lot of other references to this error using Google but I'm having trouble making sense out of how they apply to what I'm doing.
Here's the VBA error I'm getting at compile time: "Function or interface marked as restricted, or the function uses an Automation type not supported in Visual Basic."
VBA Code that causes the error:
'ftp is also a com object created in code not posted here Dim f() As wooxter.FTPFile f = ftp.GetFileList 'Returns an object array of type FTPFile
I have a managed class that uses a COM that looks like this.
[Code]....
Since I am using an unmanaged dll through a COM-Interob dll I am wondering if I need free the innerobj manually or if the gc is smart enough to do it automagically if I call ReleaseObject() My class implements IDisposable and I do the following atm: Runtime.InteropServices.Marshal.ReleaseComObject(myobj) Do I need to take care of releasing all inner objects that are created by the COM Object or not? And If I do have to do it, does the order matter (first inner then parent vs parent then inner)?
Trying to replace Cells(RowIndex,ColumnIndex).Value() calls by row-wise references for performance, I permanently fail at referencing the result. Starting with Excel Interop - Efficiency and performance, which contains the tip to use get_range, i.e.
However, referencing Values with two dimension indices always returns an "index was outside the bounds of the array" exception. Inspecting the array with the debugger shows a nice 2-dimensional array which should has 17 elements on the second dimension, so Value (0,0) should indeed be a valid reference -- but it isn't:
The debugger lets me inspect Value, I can also drill down to Value(0,0) and see the correct value, but re-evaluating just that element, i.e. inspecting "Value (0,0)" returns above message.
I have a C++ dll that contains a callback. The callback has one parameter that is passed in and one parameter that is passed out. The parameter that is passed from C++ is a variant. So, we are going from a variant in C++ to an object in VB.NET. The function works. However, It seems that there is a memory leak on the VB.Net side. This must be a Marshaling issue. I have tried to use the MarshalAs Functions, but to no avail.
VB.NET Declare Function EnableWriteNotification Lib
I have an application that creates desktop shortcuts. To do this I have to reference the Windows Script Host Object Model. When I add it as a reference, it always creates the DLL, Interop.IWshRuntimeLibrary.dll, in the objx86Debug directory, then references itself to it, rather than looking at wshom.ocx. Even if I add reference wshom.ocx it reverts to saving the file in the objx86Debug directory. The problem is if I move my application to another computer without that DLL being present, the program fails to run.
I've got some functions I need to call that are in some DLL files that have been written in Delphi 5 in a VB.NET 2005 application. I'm able to use the DllImport function to access the functions just fine; however, I'm having an issue with the Delphi string data type and passing it to and from the .NET application.
[Code]...
It takes two string parameters and one double. I can call this function from VB.NET just fine, but it will error as soon as it tries to use one of the string variables (so in this case, when it passes them to another function) and I've found that the string values in Delphi are junk when they've been passed to .NET. I'm guessing that the string objects behave and/or are encoded differently between .NET & Delphi 5, and that I have to apply some sort of Marshaling to the function parameters in .NET, but I've tried all of the different types of marshaling and nothing has worked. Unfortunately, I haven't been able to find anything about this issue on the internet.
Does anyone know how I can call this Delphi function from .NET and have it pass the string values in a manner so that they won't be corrupted when stored in Delphi?
I'm having trouble using a COM based DLL in that one of the parameters is of type VARIANT.
The C++ definition of the structure is as follows:
typedef struct CSimData { DWORD dwSigId;
[Code].....
From debugging i've been able to determine that the COM server is getting no value in vValue. Is there some sort of Marshaling that needs to be done to be able to set that VARIANT up on my side so that it can use it?
I am trying to get some data from a C Dll via a structure and I am getting incorrect values back. I tried a couple of examples I found but they do not work. Since I do not know the proper way. I do not know how to fix it. Can anyone give me any advice, hints, redirection or any assistance what-so-ever. I've been struggling with this for weeks.
I have to create an array of structure type in VB.net. but I am getting error while marshaling this error. I have to pass this array of structure type in to Dll function. Code: Structure declaration: <StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Ansi)> _ Public Structure dx_entry <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=10)> _ Public dx As String [Code] .....
I am getting the following error: An unhandled exception of type 'System.ArgumentException' occurred in Audit_Demo_2307.exe Additional information: Type dx_entry[] can not be marshaled as an unmanaged structure; no meaningful size or offset can be computed.
I have been trying to use vb2008 to automatically update CustomDocumentProperties fields that I have set up within a pro-forma document. I can load the Word application and word document without problems.I want to update the CustomDocumentProperties fields with data read from a dB. To do this I am assuming that I need to iterate through the CustomDocumentProperties fields within the word document and when one is "found" that matches the data I wish to merge then assign the dB value to the field.The problem is that I am getting an exception error when I try to reference the document customdocumentproperties
"Error : Unable to cast the COM object of type 'System._ComObject' to interface type 'Microsoft.Office.Interop.Word.CustomProperties'. ...... "
my code looks like;
Dim WordApp As Word._Application Dim odoc As Word._Document Dim BContinue As Boolean = True
Basically I've coded an Excel 2007 project in VB.NET 2010 that allows you to create charts with a fair amount of interactivity. I want the user to be able to save and reopen this workbook and still have that interactivity in any already-created charts, so they don't have to re-create them.
When I create the charts, I use Sheet1.Controls.AddChart(...), which returns a Microsoft.Office.Tools.Excel.Chart with which I can handle events and such. However, when I reopen the file and look through the Sheet1.Controls collection, there are no Chart objects. Accessing the charts through Sheet1.ChartObjects.Chart gives me Interop Charts, when I need the Tools Charts.
I just wondered if you can or can't save arrays using the settings system object. There seems to be no way of entering it at designtime. It seems implied you cannot create new user settings.subobjects at runtime. I'm looking to find the easiest way to save a populated array of PictureBox's. If the only way is a self/custom made/managed .ini file then I need to know so i can start on that but I was hoping to use some of all this phaff in the new frameworks usefully.
In VB6 I load a recordset containg all of the records (6 fields per record)in a table into an XArray and then manipulate the records in the array and then write them back to the original table. The array issorted by the first field (1 to maybe 8000 or more) I need to find records in the array by an ID field and then move them (because of some external criteria that happens many times) from say number 400 to number 375. Then all of the other records between 375 and 399 were renumbered up 1 to fill the gaps left by the move.
The XArray worked well as it could find and also move to a next record easily to facilitate the revisions to each record quickly. Everything is done in VB6 in code and nothing visual needs to be shown to the user until say 2000 of these external changes are complete. What is the best, most efficient way to do this in the .Net framework in VB2010. Datasets, Dataviews. tableadapters, arrays. enums ?
My assignment is to have a user enter in big integers using what i think is two parallel arrays. I got this far but now im stuck. I think i need to actually convert the text box input into an array but i do not know how to do that. I am all over the place in this project.
'Created/ Revised by: Jessica Falcetta 'Cap 204 Final Project: Big Integer Project 'Project Purpose: To calculate large integers through parallel arrays
I have a VB.net console app and I am opening a function in a dll written in fortran. I am passing 3 arrays through the function by reference. When they come back out the otherside they ahve all tunred to arrays of only one element And that element is 0.I read on the internet somewhere that when doing this kind of thing it is a good idea to only pass the first element of the array into the function.I tried changing my function declaration to accepting single elements rather than single dimensional arrays, and now the arrays are the same length before and after the function call, but they don't seem to be changing at all, so i'm not sure that this is working
the statement Dim state(49) As String and maintain a list of certain states. The list of states should always be in alphabetical order and occupy consecutive elements of the array. The buttons in the program should give the user the following options: (a) Take the state specified by the user in a text box and insert it into its proper position in the array. If the state is already in the array, so report. (b) Take the state specified by the user in a text box and delete it from the array. If the state is not in the array, so report. (c) Display the states in the array. "
Private Sub states_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load state(0) = "Alabama"
I was wondering if anyone knows a built in method ( LINQ say or a LAMBDA expression or other way ) that you can compare2 arrays - collections that would be valid for an equivalent 3rd array - collection which is a combination of the 1st two.
I am somewhat new to object oriented programming and am attempting to flatten a Linq object hierarchy by using a shim class.how to initalize a derived class with property values from a base class?I have two objects, a base object with about 100 properties, and a derived object which inherits from the base object and adds a few additional properties beyond those of the base object. My simple constructor creates the derived object, but I am looking for a way to initialize the derived object properties with values from the base object.Right now I am using reflection to iterate over the properties individually and I suspect there may be a better way. The following example shows my shim class constructor for the derived class, and two properties:
newProperty1 - a new string property of the derived class
flattenedProperty2 - a new string property of the derived class, copied from a 2nd-level object of the base class
Code example:
Public Class derivedObj Inherits baseObj Private _newProperty1 As String[code].......
Is this the correct constructor approach to flatten the object hierarchy using a shim class? My second question relates to initialization of properties in the derived class. The constructor above creates the derived object, but what is the best way to initialize the derived object properties with values from the base object? The following code uses reflection to iterate over the properties individually, but I suspect there may be a better way.
Code example:
' property names are in the string array fieldNames
'baseObjQuery is an ienumerable of baseObj
'derivedObjList is a list of derivedObj[code].....
Is there a simple way to initialize values for the properties in the derived object based upon the values of the common properties in the base object?
This might be a bit of stupid question but I need some clarification. I'm somewhat new to .NET and have created a EXE that had to reference an existing COM DLL. In doing so, Visual Studio 2010 automatically created an "Interop" DLL that it needs/uses to work with the legacy COM DLL.
I have deployed my project and included this Interop DLL with it (in the same folder) and everything is working fine. However, I have other applications that will need to use this same legacy COM DLL. Is it okay to reference it they same way in each application and keep deploying the "Interop" DLL with each application? Unfortuantely, all of these small applications go in the same folder and each use the same Interop DLL (so it will already exist there if it's used by another app.) I'm forced to having them in the same folder because these applications are being called as a way of customizing a parent application. As such it only looks in it's local folder when it wants to run a "custom" app. I'm just concerned if one the EXE's is ever removed and they take out the Interop DLL, then the others that still depend on it will fail.
So, I was wondering if it is possible or a good idea to put that Interop DLL in the GAC? I went ahead and installed the Interop DLL into the GAC and then removed the Interop DLL from the folder where my EXE runs and it failed to work. I get an error that says "Could not load file or assembly". I'm stuck on getting this working.
Do I need to reference the Interop DLL in my project differently such that it's now from the GAC? or Do I need to add something to my .NET code like Assembly.Load to make it work? Do I need to create that Interop DLL myself using TLBIMP?
What is COM Interop? Please remember to mark the replies as answers if they help and unmark them if they provide no help.Welcome to the All-In-One Code Framework!
I am using Interop to read and write to excel but I'm having some problems writing to excel... When I enter the information I need to be written on the excel in an inputbox, this pops up "COM object that has been separated from its underlying RCW cannot be used."Heres the Code:
Code: Private Sub editmodelbtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles editmodelbtn.Click
I am trying to use a 3rd-party Interop assembly called SmartWIM.
I have added it as a reference and added an Import statement
Imports SmartWIMLib
I then initilalise it with
Dim objSmartWim As New SmartWIM
All pretty standard stuff, I've done this countless times with Interops. However, whenever I try and use any methods I get the following error [code]...
I'm kinda new to using VB.NET and certainly with the Excel Interop.I have the impression that I'm doing something wrong in these simple procedures. I keep getting errors on them:
[Code]...
The first procedure fills a combobox with all the worksheet names of the workbook.The second procedure copies all cells in the selected worksheet to an array.The error is the following: System.NullReferenceException: Object reference not set to an instance of an object.I think the error is in the cleanup part, when I set the objects to nothing and close everything. Can someone confirm if this is good or wrong code and maybe point me in the right direction?
I Programe a COM Library in VS2008 to use in Excel , but I'm stuck with an error that I don't understand.
I use this two classes , that compile and register OK. One Class QBitems return a nongeneric collection of QBItem but when I tried to use the Add and/or Remove Method, I receive the following error in Excel VBA :
Run-time Error '438': Object doesn't support this property or method.
I added a class (SImpleClass) in the library and I called from VBA it returned the QItems collection without problem.
NEW: When I replace the QBItem object with a string in the Collection QBItems everytthing works OK. It looks like interface doesn't like to pass an object like QBitem class
Excel/VBA: Sub Pru() Dim obj As New CollectionCOMClass.SimpleClass Dim Itms As New CollectionCOMClass.QBItems
