C# - Casting System.__ComObject To Known Type Reflection
Sep 15, 2011
I am trying to create an Excel file using reflection. The reason, the application will be running on many machines some of which may or not have excel installed. I decided to embed the "Microsoft.Office.Interop.Excel.dll" and via reflection generated the excel spreadsheet. The code I am trying to resemble is:
Code: Dim dom As New DOMDocument30 dom.async = False dom.Load(serverAddress & "/App/filelist.jsp?type=content") For i = 0 To dom.childNodes.item(1).childNodes.length - 1 downloadfile(dom.childNodes.item(i), mcount, currentpath) Next
The above code is activated upon clicking of a button. i have the server address declared. and using the domdoc to load the jsp file to generate the xml data. and using for loop, i call the download file function which accepts the following parameters
Code:Public Sub downloadfile(ByVal domdoc As Xml.XmlNode, ByVal totalcount As Integer, ByVal currentpath As String)
The totalcount and currentpath work fine, but when i pass in the dom.childNodes.item(i) , error pops up.
--------------------error message------------------------------------------Unable to cast COM object of type 'System.__ComObject' to class type 'System.Xml.XmlNode'. 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.-------------------------------------------------------------------------------
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 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 working on a card game, and i get this werid error:
A first chance exception of type 'System.Reflection.TargetParameterCountException' occurred in System.Windows.Forms.dll
The code that is cousing this error is:
Private Delegate Sub ShowcardDelegate(ByVal test As String, ByVal objtest As Object, ByVal value As Boolean) Private Sub Showcard(ByVal test As String, ByVal objtest As Object, ByVal value As Boolean) If objtest.InvokeRequired Then
I have had several occasions recently to access a specific class several times over a relatively small time frame.So I've been storing the value of the class in Session and trying to access it on page load, if it's not available creating a new instance and storing that in session.
So instead of constantly replicating the same code for different classes on different pages I'm trying to create an extension method to do this for me.
[Code]...
I'm stuck on what to do when I make my new instance of my class (it would have to have a New() sub)
I'm not sure where to go from here... or even if this is the best way to do it.
I'm passing a type name and some parameters from C# code into a navigation framework written in VB. The navigation framework looks for a constructor on the type that matches the parameters passed in using Type.GetConstructor(Types()). The constructor that I'm looking for expects an array of integers Integer() in vb. But it gets an array of System.Int32. I've gone so far as to try this:
[Code]...
And the VB code still sees System.Int32 on the other end, which means that it doesn't find the constructor.
I have been working with System.reflection namespace and i have problems to get value of properties in system.__ComObjectMy objective is:obtain a collectionfor each object in collection get the propertie (example ID)
I'm wrestling with this treeview control. I have extended the TreeNode class to attach some extra data to the node. Basically, I added one property:[code]Is there a way to cast from a base type to a derived type?
Delegate Sub UpdateTextHandler(ByVal recbuffpass() As Integer)
Private Sub someSub() Dim f As frmMain = My.Application.OpenForms("frmMain") f.Invoke(New UpdateTextHandler(AddressOf f.UpdateTextMethod), New Object() {recbuf})
When writing some Outlook code in VS2005, I came across a situation that, to me, does not make any sense. For reference, the version of Outlook running on this machine is Outlook 2003.The program I'm writing is designed to iterate through the emails in the inbox, to identify certain types of emails based on their subjects and bodies, and then to generate new emails based on the existing ones. However, the problem that I'm having is with simply iterating through the collection of items that comes from the Inbox folder. Specifically, what happens is that this line consistently fails on items that should be processed:
Hmmmm having discovered that using the mciAPI doesn't utilise 5.1 sound, but using a virtual WMP does - I started a new approach to my multimedia project using some code from the net. BUT I keep getting exceptions (particularly with type casting). In the subrountine 'Player_PlayStateChange'.
The listing (see below) is now well commented by me. Can anybody please help concerning the damn annoying exceptions and stop me pulling my hair out.
I have an InvalidCastException Error in my program. The program is that i try to insert an employee record into a database table after getting the details from a form. I've used Money data type is SQL Server for salary and SqlTypes.SqlDecimal data type in employee template class. i've used a stored procedure to pass the values and i add the basic value by passing a parameter by the method
Dim prm8 As SqlParameter = com.Parameters.Add("@basic", SqlDbType.Money) prm8.Direction = ParameterDirection.Input prm8.Value = emp.Bsc
I've used the money datatype itself even in the stored procedure variable.I get the following error.
failed to convert parameter value from sql decimal to decimal Even if i use prm8.Value = Convert.ToDecimal(emp.Bsc)
I get an error Unable to cast object of type 'System.Data.SqlTypes.SqlDecimal' to type 'System.IConvertible'.
I am getting this error when I am tring to load string type to data table)
Using connection As New SqlConnection("connectionstring;") connection.Open() Using Command As New SqlCommand("SELECT ClientId,forename,surname from t_clientdetails
I'm creating a student evaluation form in a repeater that should submit the evaluation responses and update the SQL database, but I keep getting the error mentioned in the title. I'm coding in ASP.Net using VB.
I am getting a really bizarre error and it makes no sense at all.Basically I have a user entity which has a Password property. This property is of Type Binary, the server data type being Binary(512).I am reading this value in and converting it to a byte array. However whenever I run my code I am getting a completely unrelated error of Unable to cast object of type 'System.Guid' to type 'System.String'.This strikes me as very odd since I am not using a property or variable of type string or GUID anywhere in this procedure where it falls over.
The code is below:
Public Shared Function ValidateUser(ByVal username As String, ByVal password As String) As UserValidationMessage Using db As New EntityMapDataContext Dim u = From user In db.Users Where user.Username = username
When testing the followng code from Mastering VB2010, I get an Unable to cast object of type 'System.String' to type 'System.IFormatProvider' exception.In the Button1_Click event code Dim strmOut As New System.IO.StringWriter(SaveFileDialog1.FileName)the 'SaveFileDialog1. FileName' is underlined with a green squiggle and displays the following tool tip:Runtime errors might occur when converting 'String' to'System. Iformat Provider'.This is apparrently the problem but what does it mean and how do I fix it to get the code to work? 'Code being tested that runs the exception:Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click.[code]
I have a bit of trouble right here, I am trying to get the data from the site and input them in the listview. Well, when my main app start to load through on debug, then it start to display a warning. The warning is: Unable to cast object of type 'System.String' to type 'System.IFormatProvider'.
I'm getting a sporadic 'Unable to cast object of type 'System.Int32' to type 'System.String' Exceptions at .SingleorDefault() in the below code. It works 9/10 times but randomly it throws an exception. I made sure that SettingID that i'm passing has no Null Values and the data in the table always exists for the settingID, and i'm always passing SettingID as Integer.