I create an application in both C#.NET and VB.NET
When I inherit a C# class in VB I want to be able to set an instance of the VB class to be equal to that from a C# instance.
public
class
SomeClass
[Code].....
I'm using WMI code and VB 2008 to see NIC status. So far the queries are working, but the methods aren't. For example, I'm trying to set a network card to use DHCP, I get invalid function with this code:
Dim classInstance As New ManagementObject("rootCIMV2", "Win32_NetworkAdapterConfiguration.Index='7'", Nothing)
Dim outParams As ManagementBaseObject = classInstance.InvokeMethod("EnableDHCP", Nothing, Nothing)
The program below trhows an error in the line "mTable2 = mTable.Copy". The error is: "Unable to cast object of type 'System.Data.DataTable' to type InherintanceQuestion.InheritedTable". This is because mTables is an instance of the InheritedTable class which inherits a DataTable and mTable is a DataTable. So, is there any way I can create the mTable2 to the mTable.copy to the mTable.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code].....
Private
Sub cmdExit_Click(ByVal
sender As System.Object,
ByVal e
[code]....
I recently wrote an inherited picturebox control. From within the control inside methodI I call Me.Invalidate to fire the control onpaint event. But onPaint does not fire.
View 2 RepliesThis is more of a conceptual question than anything.
I have a base class called "RawReader".
It sets up the framework for classes to inherit it and read in specific data systems.
For example, I want an app read in a known format of FoxPro database, a CSV file, or a SQL database (there is about 8 more formats currently), then transfer it over a webservice and create a SQL database from it.
I have everything working with CSV, FoxPro, Access, Excel, etc... Easy enough.
The classes that inherit RawReader, like RawCSV, RawFoxPro, RawAccess all return a struct that contains a dataset as one of the members. The dataset contains the data from the raw system. The webservice receives this struct and creates sql tables and loads the data into it. This has already been coded and works great.
My issue now comes to reading in SQL. Obviously, I could follow the same path, read the remote SQL DB into a dataset, transfer the dataset as above, etc... My "issue" comes in where I feel like it doesnt make much sense to transfer a SQL db to a dataset, transfer it through the webservice, and then try to programmatically recreate the SQL database. I feel like I lose a lot of the granular details from the SQL database (field sizes, extended info, etc..) It seems easier in practice to just create a backup of the database, convert it to a stream object and transfer the backup over to the webservice. But this is where the problem lies...
Since all of the classes inherit from the base class, they are set up to return a DataSet. The hack-ish way would be to just add a stream object to the return struct and in my webservice add other code to make a special case for SQL sources, but I was trying to avoid that.
Any thoughts on the "proper" way to go about something like this?
Object aggregation of inherited classes
View 3 RepliesSeems like you should be able to Suppress Properties in inherited classes. How do you do it?
View 7 Repliesi've finally got round to learning about classes and inheritance, but i'm not sure how to proceed. i have a base class Employee, which is inherited by 2 derived classes. how do i use the same Employee class in both derived classes? obviously if i write a sub new for both of them + declare a new Employee class, they won't be using the same class. heres my Employee class:
[Code]....
I'm getting an invalid cast exception but I'm not sure why, here is the list of my conversions.
SQL -> VB.NET
char(4) -> String
varchar(50) -> String
tinyint -> Integer
char(1) -> Char
bit -> boolean
[Code]...
see from the following function why I would be getting an "Invalid Cast Exception"? More specifically this is the error "Conversion from string "yyyyMMdd" to type 'Integer' is not valid." I am trying to convert a DateTime value from the database to a String with the format "yyyyMMdd" so for example October 22, 1985 would be "19851022".dbReader(fieldName).ToString("yyyyMMdd")Here is the entire function ...
Private Function GetDBReaderDateValue(ByVal dbReader As IDataReader, ByVal fieldName As String) As String
If dbReader(fieldName) Is DBNull.Value Then
[code].....
How do I get rid of invalid cast expression from the Values in the Combobox to fit in the equation in examgrade? I tried to resolve it by looking it up on MSDN, and the like but couldnt figure it out.I tried using Examgrade = ().ToString but that did not work.FYI this is my first real program, I successfully made this once in C# but deleted the source files, so this is Visual Basic and a hell of a lot easier to get this far.The asterisks mark the problem line
Public Class Calculator
Dim quarter3 As Integer
Dim quarter4 As Integer[code].....
I have a parent class that is also a factory. For example:
Public Class Factory
Public Function clone() as Factory
' Some logic here
[code].....
i know this may seam odd but I'm getting an error navigating through a datagrid of an invalid cast. The trouble is it is of the same types!! I working on customising some Sage code and in the form there is a datagrid that is populated by a series of Sage.Accounting.Stock.TraceableSOPAllocationItems (a batched stock item allocated to an SOP).
I want to give the user some further information on each item so they can decide which batch and bin to use. I want to go through each item in the grid and then go find this extra information for it. the trouble is when I go to navigate through, My VB.Net code throws the error.InvalidCastException was unhandled by user code, Unable to cast object of type 'Sage.Accounting.Stock.TraceableSOPAllocationItem' to type 'Sage.Accounting.Stock.TraceableSOPAllocationItem'.
[Code]...
I need to use two Invalid Cast Exceptions on one try. I need to to appear when txtNight or when txtRate has an invalid value.
Try
decCharges = CDec(txtRate.Text) * CDec(txtNight.Text)
lblCharges.Text = decCharges.ToString("n")
[code]....
I've seen some other responses about this and they talk about interfaces but I'm pretty sure you can do this with classes and base classes but I can't this to work.[code]....When it tries to convert whatever Activator.CreateInstance(t) returns to the base class of type Behavior I'm getting invalid cast exception. That type should be of CharacterController which is defined as a child of Behavior so why wouldn't it let me cast that?
View 2 RepliesI am getting Invalid Cast Exception was unhandled.Conversion from String 'abc' to type 'Double' is not valid in the following line!
If
((xlBook.Worksheets(2).Cells(iRowIndex, iColumnIndex).Value)) = avFoundKeywordds(iSearchText)
Then
The business intent is that user enters the keyword 'abc' and clicks search button . We have defined different keywords in a xls which has 1600 rows and 16 columns . so when finding abc in any of the cells ,it has to return the value of a column#4 where the name is specified !
I am trying to create the Proxy from the WSDL using wsewsdl2.exe [code]...
But i am getting Invalid cast exeption.Can someone please tell me how to i fix it?
I am using VS.net 2003 with WSE 2.0 V3 and Soap 1.1 installed.
i save image into a database correctly and now when it come to retrieving i get an error message when the photograph column is NULL.Is there any way i can check if it is null then i execute different code else it return the image.This is what i am using for now
Dim barrImg() As Byte
Dim cmdSelect As New SqlCommand("select Photograph from Personal where MyID=@ID", connect)
[Code].....
Here's my [code...]
On this line "db.jobs2surveys.DeleteOnSubmit(deleteJob2Survey)" I'm getting the following error.
[code...]
What exactly does this error mean and how can I fix this? I can't find much info on Google.
We are trying to implement a logic which we used in vb6 2 years back.User enters a business requirement in text box, we define the keywors in the script and once the button is clicked , it shld luk from the list and display a msgbox of number of keywrods found.
1. Invalid Cast Exception was unhandled error -->Warnings
2.When casting from a number , the value must be a number less than infinity -->Warnings
3.When trying to declare ,variant is not accepting and its converting it into Variant Type. Are these both same?[code]
Dim NSNSRC As String = WebBrowser1.DocumentText
This throws me an error although DocumentText does have a value, I have also tried a .tostring after and it still did not work.
Surrounding Code:
While DocCompleated = False
System.Threading.Thread.Sleep(0)
End While
[Code].....
I have declared two variables as strings strDob and strCurrentDate, Both Variables are for storing dates. StrDob is for storing Date of Birth and second is for Present date. and am executing the following code
If DateValue(strDOB) > DateValue(Date.Today) Then
and getting the error like
Invalid CastException was unhandled
Conversion from string "19/09/1987" to type 'Date' is not valid.
Error in the following code also:
iAge = (CInt(Abs(DateDiff("d", strCurrentDate, strDOB)) / 365))
Invalid CastException was unhandled
Argument 'Date1' cannot be converted to type 'Date'.
Here I need both variables as string itself. because the Dateofbirth is getting from three comboboxes.
textbox1.text = "6916092, 15195440, 16107657, 1836924, 3758726, 12566463, 7526079, 7405793, 6945974, 241502, 2296476, 5130294, 3102017, 7324121, 14993507"
ColorDialog1.CustomColors = New Integer() {TextBox1.Text}
I am getting an InvalidCastException. How do I insert the value of textbox1.text into those brackets in vb.net?
why do i get an error here?TextBox1.Text = TextBox1.Text & Str(ColorDialog1.Color)
View 1 RepliesI've got a masked text box that throws an invalid cast exception if I try to put anything in the TextChanged event:
Private Sub mtbZVal_TextChanged(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MaskInputRejectedEventArgs) Handles mtbZVal.TextChanged
MsgBox("OK!")
End Sub
Even more oddly, it throws the exception in a completely different part of the program. The masked textbox is on a form that opens when you press a button, and that's the bit that gives the error:
Private Sub cmdAddLoc_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdAddLoc.Click
If frmLocation.ShowDialog() = DialogResult.OK Then
End If
End Sub
I'm just converting a date to a string but I'm getting this error. It's not listed as one of the normal exceptions to the datetime.tostring method. Googling around, it looks like it's an actual bug where it thinks StartDate is an int--but that's no help to me, as I just need to convert the date.
dim StartDate as nullable(of date)
dim Date1 as string
if not StartDate is nothing then
Date1 = StartDate.tostring("yyyy-mm-dd")
end if
In businesslayer, there is a inherited Class Called BaseEdit which contains contractor and base properties. There are about 30 CustomEdit (inheriting classes), all of them has methods "Load","Save" and "Delete". The require for this existing system is to add a readonly user. Possible solutions considering the cost of works:
1) Modify the BaseEdit so all CustomEdit can stay the same. The system will check 'user role' in session by using httpcontext then to accept or reject the user's action.
[Code]...
I get an Invalid Cast Exception - Conversion from string to double not allowed. I don't know what to do.
Option
Strict
On[code]......
Several of my overriden Equals methods have started throwing Invalid Cast Exceptions -
Unable to cast object of type 'System.DBNull' to type Common.ResolveUser'.
This occurs when binding List (of T) (where T is of type ResolveUser in this case) to a combo.
Equals Method:
Public Overrides Function Equals(ByVal obj As Object) As Boolean
Dim i As ResolveUser = CType(obj, ResolveUser)
If i.UniqueResolveID = UniqueResolveID Then Return True
[Code]......