Unable To Cast From List(of Object) To IList(of Interface)?
Apr 19, 2011
I'm new to generics and am having some issues when using with interfaces.I'm developing with VS2008 - .NET 3.5 Ultimately, I'd like to create an interface that inherits the IList(Of T) interface and add a function definition to the derived interface that adds a new element of type T to the list and returns the index of the newly added item.
I have everything figured out but am stuck on a casting issue. If I execute the following line of code at runtime:CType(New clsObjectFactoryList(Of clsIDNamePair), ifObjectFactoryList(Of ifIDNamePair))
I am working in VB.net and have a Class, Foo, that implements an interface, IBar.I have a List of Foo's, but I need to pass a list of IBar's into a function, but I keep getting casting errors, even when I use DirectCast.My code is [code]MainWorks works, but it would be really annoying and inefficient to have to do that everywhere I want to call this function.
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 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
The latter is giving the error "Unable to cast object of type 'Object' to 'CTest'." when used:
Dim thestack As CTest() = testdatabase.getStack Where testdatabase.getStack simply returns stack(); Public Function getStack() As Object() Return stack End Function
This fixes it, but it's not ideal (for me personally):
Dim thestack As Object() = testdatabase.getStack
So if I could keep the variable as-is (Public stack() As Object) and then do something along the lines of class.stack() = CTest I should be able to do Dim thestack As CTest() = testdatabase.getStack because the object array will programmatically have changed from Object to CTest.
I am new in programming with VS2008. Nowdays I try to built a simulation of graphics movement. I use Panel to draw the graphics but I faced a problem when I want to move the object. There were a message "Unable to cast object of type 'System.EventArgs' to type 'System.Windows.Forms.PaintEventArgs'.".
Public Class Form1 Dim x, y As Integer Dim n As Integer Dim xp, yp As Integer Dim xt, yt As Integer [Code] .....
I have a base class called Schedule and three classes inherited: DailySchedule, WeeklySchedule, MontlySchedule. Now I would like to build a form in which users can modify the schedule and I have to compile different parts of it depending on whether the schedule is daily, weekly or monthly. Then I want to have back the schedule modified. Which object can I use on the form?
I thought to implement on the base class an interface iSchedule and to pass the interface to the form, but when I'm on the form constructor how can I cast the interface to the correct class? e.g. in the form constructor I will have a sched variable as iSchedule, I can see that, for example, is a DailySchedule from an interface property called Type. But how can I cast the interface to an instance of the DailySchedule class and to access to its members?
i am trying to create an sql parameter but i am having an error. it gives me an error like this: Unable to cast object of type 'System.Boolean' to type 'System.Data.SqlClient.SqlParameter'. on all of this line
Dim paramcollection As New List(Of SqlParameter) ' no error on this part but the lines below gives me an error: paramcollection.Add(New SqlParameter("@CGLCode", SqlDbType.VarChar).Value =
I seem to have broken something I get this error Unable to cast object of type System.EventArgs' to type 'System.Windows.Forms.KeyPressEventArgs'.
my code: Private Sub ListControl_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListControl.SelectedIndexChanged
I want to do something like this: Dim selectedCourses As List(Of Guid) = From item In chkListCourses.Items Where item.Selected = True Select item.Value
But I get the error: Unable to cast object of type 'WhereSelectEnumerableIterator2[System.Object,System.Object]' to type 'System.Collections.Generic.List1[System.Guid]'.
The value of item is a string representation of a Guid. I'd also like the syntax for a Lambda expression.
i write this code to work with some radio button and calculate Score for a questionare : Dim SScore AsByte = 0 Dim BTNN AsByte = 0 Dim BTNNS AsString = "" ForEach rBTN AsRadioButtonInMe.Controls If Mid(rBTN.Name, 1, 5) = "RBS01"Then If rBTN.Checked Then SScore = SScore + CType(Mid(rBTN.Name, 7, 1), Byte) EndIf EndIf Next I get this error on line 4 : Unable to cast object of type 'System.Windows.Forms.Button' to type 'System.Windows.Forms.RadioButton'. i dont know what is it and how can handle it.
I'm having a real problem with serializing data. I understand that its designed to basically copy the structure and data of a structure. In my case, I have the state of a DVD that i would like to save (persist) to disk. [Code] error: 'Error Generating XML', Inner Exception: "Unable to cast COM object of type 'System.ComObject' to class type 'DirectShowLib.DVDState'.
COM components that enter the CLR and do not support IProvideClassInfo or that do not have any interop assembly registered will be wrapped in the ComObject type. Instances of this type cannot be cast to any other class; however they can be cast to interfaces as long as the underlying COM component supports QueryInterface calls for the IID of the interface."
I am storing an array of a custom serializable class in session on my site. When a page on the site changes, suddenly it renders them invalid, and tells me that it can't cast the type to it's own type. I assume the class version numbers are changing or something?!
I'm not trying to redesign this whole process.
Unable to cast object of type 'ShipmentPackages[]' to type 'ShipmentPackages[]'.
Description: An unhandled exception occurred during the execution of the current web request. review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.InvalidCastException: Unable to cast object of type 'ShipmentPackages[]' to type 'ShipmentPackages[]'.
I have a form contain 10 checkbox. how to count total checkboxes that has been checked? i search over the internet but not found any solution. please help me. i found a code, but when i apply it on my project it says "Unable to cast object of type System.Windows.Forms.MenuStrip' to type Component Factory. Krypton.Toolkit.KryptonCheckBox'".i think i have problems with Me.Controls(on the code)[code]
Unable to cast object of type 'System.Windows.Forms.MouseEventArgs' to type 'System.Windows.Forms.DataGridViewCellMouseEventArgs'.
Private Sub NoteGrid_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles NoteGrid.CellContentClick Try
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.
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'"?
