I am trying to inherit System.Data, but when I use Inherits System.Data I get a "Type Expected" error. Is there a way to do this? or is the question I have been given meant to make me realise that it can not be done?
View 4 RepliesI would like to utilize classes that inherit the System.Data name space.Specifically, I would like to have classes CarColumn, CarTable, and CarSet derived from DataColumn, DataTable, and Dataset respectively.I would like to be able to add additional properities to each class. As an example this is how I would like to reference items within the classes:
CarSet.CarTable(0).Columns(0).foo
CarSet.CarTable(0).bar
I know that VB.Net is not capable of Multi-Inheritance.
I have written methods to override the LoadPageStateFromPersistenceMedium and SavePageStateToPersistenceMedium methods. now the problem is that i am using a masterpage, so how do i maintain using my masterpage and still inherit from System.Web.UI.Page?
Bear in mind that the .vb Code behind the masterpage already inherits System.Web.UI.MasterPage. Anybody know how i can "properly" override these methods in a MasterPage?
Is the only way to create custom exceptions to inherit from System.Exception?
I wish to create a class that can be thrown as an exception but i do not wish to inherit from System.Exception because i have a base [Object] class in my library which all my classes should inherit from and i wish my custom exception class could also inherit from it.
How to create a class which inherits from a data type, specifically from Char data type? I just want to add one property to it. If it's not possible, are there any other ways to accomplish this?
View 2 RepliesI have the below lines of code :I am getting the error as mentioned in the Title above.This error has come after converting a C# Code to VB.NET Code which is mentioned below:
C#:
public override IChannelListener<TChannel> BuildChannelListener<TChannel>(BindingContext context)
{
if (context == null)
[code]....
i was trying to inherit System.Type. this is what i have:
[Code]...
and anyway the real problem is that inheriting System.Type without declaring my derived class as 'MustInherit
I get an error when I try to build my project.'SSLAccessFiltercannot' be used as an attribute because it does not inherit from 'System.Attribute'. [code]
View 1 RepliesIs this possible? Must be surely but I've tried and come up short. I've created a very basic class (person) with 2 public properties, forename, surname. My user control is databound to this class and has 2 textboxes to store the properties.
I've built the control and can add the user control to a windows form but how can I add to a new user control (Staff) which will show my 2 existing textboxes and I can add dateJoined datepicker also??
I am trying to perform a simple bound connection between an Access database and a text box on a form. This is actually Chapter 18 of the "Microsoft Visual Basic 2008" book.I get the same error message when trying to create my own project "MY ADO Form" or the "ADO Form" project supplied from the DVD provided with the book. I am running the 90 Day Trial Version of Visual Studio 2008 with SP1 and Net 3.5 SP1.
My operating system is the 64 bit Version of Vista with all updates.The error when I try to run the application in the debug mode is:"A first chance exception of type 'System.InvalidOperationException' occurred in System.Data.dll"and as a result no data shows up in the text box from the database and the data selection bar is grayed out in the form. The underlying database "Students Data Set" appears to be fine as I have seen the correct data for the fields "Instructor" and "PhoneNumber" prior to running the program and when connecting with the database.
I've spent a substantial amount of time trying to figure this out, but I keep getting the same error
A first chance exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll
A first chance exception of type 'System.NullReferenceException' occurred in project1.exe
This happens when I try to use the DataReader.my code is
Public Function Identification() As List(Of Integer)
Dim returnIndex As New List(Of Integer)
Dim dbCount As String = "SELECT Bookingid FROM bookdetail WHERE Date =" & getCurrentTimeString() & " 12:00:00 a.m."
Dim count As Integer = 0
[code]....
i need to clear this error
A first chance exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll
I am just trying to get the system to open a database and I get this error:
A first chance exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll
here's the entire code of the main form
=======================================
Imports System
Imports System.Data
Imports System.Data.SqlClient
[code]....
the error is generated at the open method note* this same code works fine in another computer, the main difference is that this one has a 64 bit OS.
i am trying to connect to an MS Access database and I am getting an erro message on the following line of
searchtable_command = New SqlClient.SqlCommand(searchtable_string, testsearch_connection)
Error:'System.Data.Odbc.OdbcConnection' cannot be converted to 'System.Data.SqlClient.SqlConnection'.
Here my connection string:
Dim testsearch_connection As New Odbc.OdbcConnection("Provider=MSDASQL;Driver={Microsoft Access Driver (*.mdb)};Dbq=C:CesarAccessdatabase.mdb;Uid=admin;Pwd=;")
What am I missing?
I have a problem with an application I have written. To keep it simple, it does heavy math calculations. If the results meet a specific criteria, it is written to a text file on a line-line-basis.The problems is, if I go look at the data files, I will find non-numeric symbols mixed in with the numbers. Sometimes it is a question mark, "?". Other times, it is control or extended characters that Notepad or Wordpad cannot display. They can be mixed into the numbers, like so: 215x7 or 8948x, where "x" is the odd character. I thought the problem may have been my use of "DataFile.Flush". I removed that, but still have the corruption.
Below are my declarations and code fragments:
Dim Number as ULong
Dim DataFile As System.IO.StreamWriter
DataFile = My.Computer.FileSystem.OpenTextFileWriter(FilePath & fName, False)
DataFile.WriteLine(Number)
The first time I had a problem, I thought it was my use of "Cstr()" in the WriteLine statement, with "Flush" as I stated above.I do not know if this is a situation internal to VB2008, or external, like hard drive buffers writing.
VB EXPRESS 2008. I am getting random Users that are receiving this error during install? for some, if they reboot, it works...for others no good.
I have looked and tried all sorts of things.. made people go to net 3.5 sp1, removed the add desktop shortcut, removed all unused refs.. etc etc..
I can seem to make it stop? I have read it has to do with the OneCLick? what is that? can I just turn it off?
Do While rdr2.Read()
Dim var1 As String = rdr2.Item("Week").ToString
Dim var2 As String = rdr2.Item("L1").ToString
Dim var3 As String = rdr2.Item("L2").ToString
It generates the following error: A first chance exception of type 'System.Data.SqlServerCe.SqlCeException' occurred in System.Data.SqlServerCe.dll
Interestingly, if I use a numeric value for the variable it for LSArraytemp, it writes to the database no problem at all.
My colleague gave me a DLL that manage all database business. I wanted to invoke a function that uses Stored Procedure and return the search result. In the function receive a parameter type in ystem.Data.IDataParameter[]. Below is my codes.
[Code]...
I am trying to export a dataset to a csv file
VB
Private Sub ExportDatasetToCsv(ByVal MyDataSet As DataSet)
Dim str As New StringBuilder
For Each dr As DataRow In MyDataSet
[code]....
I am getting an error on this line: For Each dr As DataRow In MyDataSet The error is Expression is of type 'System.Data.DataSet', which is not a collection type.
I have a function (on vb.net) to get a data from a XMLWebService:
[Code]...
I added this lines in the form load of DataGridPrinter by Merrion in the codebank..[code]Unable to cast object of type 'System.Data.DataViewManager' to type 'System.Data.DataTable'.
View 2 Repliesevery time i run this code i get the same error
Unable to cast object of type 'System.Data.DataTable' to type 'System.Data.DataView'.
the code is
Dim plmExcelCon As New System.Data.OleDb.OleDbConnection
Dim cmdLoadExcel As System.Data.OleDb.OleDbDataAdapter
Dim PrmPathExcelFile As String
[Code]......
This is driving me mad! This is my code and I have attached my parameters below with my error. What on earth is wrong.
[Code]...
I have a user control that inherits the FW ListView and I need to dispose of two objects when the form's disposing of it's objects. Here's what I've concluded already, am I on the right track?
[Code]...
Does anyone know why on earth in my linq to sql designer classes, that I am getting type not exist for any system, system.data, system.data.linq nameapces?I am trying to convert a website to a web application and this has me stumped. In order to create an object I have to use the Global. prefix on all the namespaces.
View 6 RepliesI am using VS 2008, Office 2007, and Win7 Home Premium on my system.I have a simple application which should be a breeze to build. All I am attempting to do is pull data from an Access database with four small tables into a data grid on a windows project. Should be simple, set up the data connection, choose a datagrid from the table in the data source view, drag it onto the page and done, right?I can't get it to work. It will all work fine until I attempt to run or debug the project. The data will not show up. The data grid does, but I get this error: A first chance exception of type 'System.InvalidOperationException' occurred in System.Data.dll
As I said, the project seems to build fine, but it will not pull the data. After the initial build I get the message that Windows will show this page in Compatibility View. Is it something with Win7 Home Premium, or a setting somewhere?
I have a windows service written in .NET 2.0 that will run every 5 minutes and executes bunch oracle SQL/PLSQL scripts based on time/validation, it throws the above said error some times against some SQLs, the same SQLs run fine at later point without any error, I have no idea what is going on with the app. I am not sure if this has any thing to do with oracle connection pool as I am properly closing the connections after every SQL execution.
Exception:
System.Exception: Unexpected return code: 1 at System.Data.OracleClient.DBObjectPool.GetObject(Object owningObject, Boolean& isInTransaction) at System.Data.OracleClient.OracleConnectionPoolManager.GetPooledConnection(String encryptedConnectionString,
[CODE]............................
I made a simple sql ce database with one table with the data explorer. Then I added the reference System.Data.SqlServerCe.dll to my project and I added this code:
Imports System.Data.Common
Imports System.Data.SqlServerCe
Public Class Form1
[Code]...
What do I wrong? The sql server ce (3.5 sp1) is fully installed with the vb express edition.
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 have a utility that is a simple exe that is not installed compiled with VS2005 and works well. But when I upgraded to VS2008 the utility can no longer locate files in the active system folder. I have UAC turned off and am logged in as the Administrator and it still can not locate a file that I can see in Windows Explorer. The file I am looking for is PakMgr.exe.
View 1 Replies