Casting Early Bound Object Type Into Late Bound Object Type?
Jul 5, 2010
I've got a piece of code in a project (MyProject) that contains early bound object from a referenced assembly (We'll call it CommonAssembly):
Dim myObject As CommonAssembly.MyEarlyBoundType
now I have another assembly that is dynamically loaded because it is not present in all projects:
Dim myLateBoundObject As Object = AppDomain.CurrentDomain.CreateInstanceAndUnwrap("Utils", "Utils.MyLateBoundType")
MyLateBoundType derives from CommonAssembly.MyEarlyBoundType, and I want to cast myObject to myLateBoundObject and then programmatically invoke the additional
I have a datagridview that is bound to a list object of a custom type via a BindingSource. From everything I've read, I should be able to click the column headers and the rows sort, This doesn't happen for me. Sortmode is set to automatic and the column headers aren't set to be used for selection so it should work.
I know that I could sort progamatticly but that seems a little bit of a waste given that I should just be able to do it by default.
I have written a small program to aide my business and the program works fine. But while compiling the code it shows a lot of warnings like the following."late bound resolution; run time errors may occur""implicit conversion from 'Object' to 'String'." Where am i going wrong. Even though the options strict off removes the warning I want to correct the warnings.
Private Function ledgerMasterFullName(ByVal i As Integer) As String Dim fullName As String Dim vObj As Object
Unable to cast object of type 'DynamicTreeNode' to type 'DynamicTreeNode'.
I have an inherited TreeView with an inherited class called DynamicTreeNode inside it. I am trying to loop through the DynamicTreeNodes in the TreeView.Nodes property which is causing this error.
My form closes whenever I insert an object that has a data bound in it. The object I'm trying to insert is a textbox from the data source window (drag n drop). I've checked on the database and that the table has records in it.
I've tested it several times because I cannot believe it. If you put a late bound project in the same solution as the calling project, you can debug the late bound project !
You can even put breakpoints in!
@#%ing amazing. Top marks to Microsoft. I don't know if this is by design, or a side effect of how the debugger works, but I don't care because it makes writing late bound projects so much friendlier.
OK Cor, you can go ahead and rubbish late-binding now.
I am implementing IMAPI2 into my vb.net project but ran into a wall. I am getting the message Unable to cast object of type 'IMAPI2FS.FsiStreamClass' to type 'IMAPI2.IStream' when trying to start the burn. I googled around and found this is something that microsoft hasn't fixed.. which basically renders IMAPI2 useless in vb.net.
I found a post on codeproject.com by eric hadden who combined the IMAPI2.dll and IMAPI2fs.dll into an c# interop file. I also see the IBURN interop in microsoft SDK samples. I'd like to use either, but it's in c# and I'm using vb express. Does anyone know a way to get the interop into visual basic or a way around "Unable to cast object of type 'IMAPI2FS.FsiStreamClass' to type 'IMAPI2.IStream'"?
I'm having a problem with converting from one source type to a destination type. I have a form with 2 buttons (button 2 uses the OpenFileDialog to have the user open an excel file set to NewFile),(button 1 takes the contents from specific cells in NewFile and arranges them how I need into oXLApp1).
The error I get is "Unable to cast object of type 'System.IO.FileStream' to type 'Excel.Application'." in line 14 of the code below.
Public Class Form1 Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
I'm new to VB 2005, the code below is actualy coded from VB 6 and just converted it to VB 2005. I'm having trouble with line that's on bold letters.In VB 6 this works just ok. By the way the error message is "Unable to cast object of type 'System.String' to type 'ADODB.Connection'." [code]
Unable to cast COM object of type 'System.__ComObject' to class type 'rjsDocMan.Folder'.Instances of types that represent COM components cannot be cast to types that do not represent COM components; however they can be cast to interfaces as long as the underlying COM component supports QueryInterface calls for the IID of the interface.The code where it is flagging the error is:
I saw this thread and I had simple answer in mind. To use custom enumerator class. So I was trying to make one for that guy, which would have one more property to check whether its has reached end or not. It would also provide current position.I'm getting an error "Unable to cast object of type 'SZArrayEnumerator' to type 'WindowsApplication1.myEnumerator'." at the line 6 [see below].However, return type of values.getEnumerator says its IEnumerator. [code]
Columns 0 & 1 are filled from a DataAdapter from Access Database and three are added. I had this working, but I changed it to check for the column "Feed" so I could add several Locations. At first this worked,but I did someething in perfecting it and it now fails after filling the first row of the datagridview (dgvFdMed).I ran a check and the table LotsTab has 8 rows filled. Column 1 & 2 are strings and the database appears they are fine. The added columns have just been created with no value. My plan is to enter the values and then use the data from the grid.
Private Sub sfillGrid(ByVal Loc As String) Dim i As Integer Dim column As DataGridViewColumn
I have 2 Child forms inside a parent. For example, FrmChild1 contains a "Friend Sub" I wish to call.I would like one of the child forms to call that sub from another child form (we will call it FrmChild2. The following code works, but when it's done going through the "For Each", I get a "Invalid Cast"
' THIS CODE IS IN FrmChild1 For Each mFrmChild2 As FrmChild2 In FrmParent.MdiChildren mFrmChild2.GuestRefresh(False) Next
Error after calls are made:"Unable to cast object of type FrmChild1 to type FrmChild2.
I have a series of API calls that are returning J# data types. I have been able to convert most of the data types (Integer, Boolean, Double, Float, etc) just fine.What I need to do now is convert a java.Util.Collection to a VB .NET collection (ArrayList)
Here is my attempt:
Public Function MakeDotNETCollection(ByVal javaCol As java.util.Collection) As Collection Dim dotNetCol As Collection
[code]....
I keep getting a runtime error "Unable to cast object of type 'AbstractListlistIterator' to type 'System.Collections.IEnumerator.
I am building a software which will be used to create a remote desktop connection. However I'm getting this error:
Unable to cast COM object of type 'System.__ComObject' to interface type 'MSTSCLib.IMsTscNonScriptable'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{C1E6743A-41C1-4A74-832A-0DD06C1C7A0E}' failed due to the following error: Δεν υποστηρίζεται τέτοια διασύνδεση (Exception from HRESULT: 0x80004002 E_NOINTERFACE)).
I am using a background worker and am attempting to use the following code. However I keep getting this error on i "Unable to cast object of type 'ObjectCollection' to type 'System.Array'."
Private Sub btnVerify_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnVerify.Click myArray = listProxies.Items() BackgroundWorker1.RunWorkerAsync() End Sub
I have some code and there are 2 errors which I don't understand I have tried all sorts...
1)The type for variable 'Index' will not be inferred because it is bound to a field in an enclosing scope. Either change the name of 'Index', of use the fully qualified name (for example, 'Me.Index' or 'MyBase.Index').
2)Function 'GetNewPhrase' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.
This program was created with vb6 to find and remove empty folders. i converted this program to VB.NET code and it isn't working like it should.. it seems to stop scanning at 'C:\documents and settings' instead of scanning other folders in other directories...Does this code look right? I can provide the entire program if needed... I just want to know why it isn't scanning like it should. Btw im switching from vb6 and trying to learn vb.net.. vb.net is a lot different..
Private Sub ScanForEmpty(ByRef vFolder As String) Dim nSize As Integer System.Windows.Forms.Application.DoEvents() If bExit Then Exit Sub
[code]....
I get this message at the bottom:Warning5 The type for variable 'FolderObj' will not be inferred because it is bound to a field in an enclosing scope. Either change the name of 'FolderObj', of use the fully qualified name (for example, 'Me.FolderObj' or 'MyBase.FolderObj').
I'd like to have an updateable DataGridView that's bound to a database-driven business object. It needs to handle all aspects of CRUD and be sortable and filterable as well.
Most of them simply bind to an object (non-database, manually filled) and do not allow you to Add, Delete, and Edit records. Furthermore, they basically never show how you would perform sorting and filtering.
I think the biggest things I'm not understanding are:
1) How do you make the DataGridView perform additions, deletions, and edits on an object.
2) How do you program your object to handle additions, deletions, and edits. Do you just need methods that use ADO.Net, NHibernate, or Linq to SQL (or any other CRUD handling mechanism)?
3) How to make this filterable and sortable.
Is this overly difficult to do or why am I have so much trouble finding examples for this?
I have a DataGridView object to which I've bound a list of objects (of type Asset) returned from a database query.I'm programming in VB using Visual Studio 2005.I want to grab two copies of the bound object (calling them oldAsset and newAsset) from the selected row in the DataGridView, update newAsset based on input from other controls on the form, and pass both oldAsset and newAsset to a function that will update the appropriate record in the DB.I try to grab the two copies like this:
Dim currentRow As DataGridViewRow = Me.AssetDataGridView.CurrentRow Dim newAsset As Asset newAsset = currentRow.DataBoundItem
[code]....
Opening a watch window on oldAsset and newAsset indicates that the appropriate values are pulled at this point. But when I try to change a property of just newAsset, like
I have a generic Class I'm using to hold information loaded from a database.I have a method which takes a DataRow as an argument, uses the object's known column name and extracts the data from the DataRow, such that:Dim loadData As T = CType(myDataRow("myColumnName"), T))works as my default assignment in most cases.Unfortunately, due to some horrifying design constraints, some of my columns may be null, and may also be taken from enumerations.This means that when <T> is Nullable(Of SomeEnumeration) the above code does not work because I can't cast 0 directly to SomeEnumeration.Zero.Is there some way to check whether <T> is Nullable(Of [Enum])? Or some way to write a method which allows Integers to be cast to Nullable(Of [Enum])?I feel like I'm forgetting something that would allow me to write one of the other of these, but my weak google-fu is turning up nothing.
EDIT: Okay, thanks to dasblinkenlight's answer below, I can detect when this circumstance is occurring, but what I need to do now is to take a type <T> which I know is Nullable(Of SomeClass), get a type reference to SomeClass and then create a new object of type Nullable(Of SomeClass) and assign that to LoadData.My problem was that I had a lot of difficulty in finding any function which would accept baseType as an actual Type.Parse accepted baseType as a parameter, I knew baseType was an [Enum] type because of dasblinkenlight's code, so I was, in this instance, able to code a solution. It's a solution which is very specific to my problem (i.e., T is Nullable(of SomeEnumeration)), but it's a solution nonetheless.
I have given reference to Microsoft HTML in COM (am using VB 2008)
"Unable to cast object of type 'System.Windows.Forms.HtmlElement' to type 'mshtml.IHTMLElement'."
I want to retrieve all the properties like the class name, html id of every object in the web browser. I am getting the above exception when i try to direct cast it.[code]...