I am working on a login page for an asp.net application. I'm making my own login and everything is working so far: I get a connection, the query is asking to return Count from the table where the username and password match the username password in the table.
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Okay, so I wrote a few custom ItemTemplates for VS2010 that implement IWizard in VB.NET (4.0). Straight forward enough. They work during my testing, but when someone else deploys and attempts to use any of them, Visual Studio throws an incredibly generic Exception has been thrown by a target of invocation error.
Stranger still, after they open up the project properties and try again... they work. Without changing anything. Anyone have any clue what is going on? Or perhaps even just a way of getting VS to give me a more specific error? I already tried devenv.exe /log but nothing out of the ordinary was there.
I have a class library that uses the IApplicationAssociationRegistration Interface [URL]
Heres the code:
Class Library
IApplicationAssociationRegistration Class:
Imports System.Runtime.InteropServices
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It worked fine till i applicated some conditions... Now my form execution stop right after a ExecuteScalar.[code]
View 2 RepliesI have a Stored Procedure which returns 10 columns of data. Using cmd.ExecuteScalar() returns the value of the 1st column from the 1st record. How can I change this so that I can return different columns, by specifying their alias/dataitem name?
I want to be able to do something like: Dim FirstName as String = cmd.ExecuteScalar("FirstName")
show me how to do an insert with EF4 VB and also how to return the ID of the inserted row?This is what I have got for edit and it works.. I have seen some very confusing ways of doing selects and edits and have found that i'm most comfortable keeping it written nice like this so that I can go back and understand what I have done.
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I want to insert a new order with an order_id and value for ExportedToOW and get the order_id back which is auto generated by the DB..
Why i got this error ?? ExecuteScalar: Connection property has not been initialized
the red section got error.
my code
Dim sql As String
Dim sql1 As String
Dim sql2 As String
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i tried this sqlcommand select max(food) from foods and i tried this dim x as double=cdbl(cmd.executescalar)and it throws the the exception {System.Invalid CastException}because the food table is empty and the max(food) is null how can i fix that because i want to take the value and add one to it so do i need to catch the error or try another conversion option?
View 2 RepliesI've got this
Public Function VendorIdOf(ByVal SimpleId As String) As String
Dim result As String = Nothing
Using drc As New SqlCommand("Select VendorId From Vendor_T Where SimpleId = @SimpleId", _connection)
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"Object reference not set to an instance of an object."
Why is that? I would expect a null value to be returned if the row does not exist.
Also - out of curiosity - how come this can be written two ways?
result = drc.ExecuteScalar().ToString()
or
result = drc.ExecuteScalar.ToString
What's up with those paren's?
currently, I use this code:
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I have an sp that deletes a bunch of rows and returns the number of rows deleted...
ALTER PROCEDURE [dbo].[DeleteChangeLog]
@ChangeEntityType bigint,
@StartDate datetime,[code]......
I'm trying to get the AutoID after inserting a record in to a DB. Does this code look right as Mydata is blank afterwards?
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I have a big stored procedure that I run. At the end its supposed to select a singe value to say if it succeeded or not, so I run the query as
Dim Command As New SqlCommand(SqlString, Conn)
Return Command.ExecuteScalar()
Which works. However there is an error in my stored procedure. I know its causing an error because the logic in the stored procedure rolls back the transactions, and after the Execute Scalar call, my transaction count is down to 0 and the my data hasn't changed. However no SQL exception was generated.
The strange part is, I changed the code to grab all the result sets from the SP to see if I could get more information. So I called the same SP like this,
Dim DAObj As SqlDataAdapter = New SqlDataAdapter
Dim CommandObj As SqlCommand = New SqlCommand(SQLString, Conn)
DAObj.SelectCommand = CommandObj
Dim DS As New DataSet()
DAObj.Fill(DS)
When I run this, with the exact same sql as before, executing the exact same stored procedure, this time I get an SQL exception because one of my nested SP calls was missing required parameters. So what could cause this? Why would running it one way produce an error and the other way have the error but not report it? Is the difference on purpose, or some kind of obscure bug in ADO.Net?
How do I implement the ExecuteScalar method to return the first element in a sorted dataset?
Here is my code:Imports System.Data.OleDb
Sub Dim oCmd As OleDbCommand
Dim strConn As String
Dim strQuery As String
strConn &= "Provider=Microsoft.Jet.OleDb.4.0;"
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It is possible to catch an exception and throw a new exception which wraps the first exception as an inner exception: [URL] Also, if I call a function and it throws a certain error, but I catch it, will the calling code's catch handler execute? If so, and it is of a higher exception type, is this not wrapping the exception? eg I can throw exception ex of type IndexOutOfRange, log it but rethrow, catch a higher up exception and do something, or I can throw a new exception and wrap an inner exception like:
View 1 Repliesi want to compare a column present in the access database BankAccount table with a field present in the form named as account......
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i have an application. which is executed after every 5 mins. i have an open connection but it gives me the following error:
ExecuteScalar requires an open and available Connection. The connection's current state is closed.
my code is something like this. I have shown where all i am using ExceuteScalar()
Sub Main()
Try
connection.open()
cmd.ExecuteScalar()
[code]....
I have a large project where we have 2-3 dll projects that are converted from VB6 to VB.NET. We have fixed all the issues that caused compilation errors, and most of obvious issues in running, so now we have basically a program up and running. The exe is created from scratch in VB.NET, using a lot of functionality from the converted dll's (including GUI forms). What I wonder is when I run the program in debug mode, I get a bunch of warnings in the "Immediate Window" saying:
A first chance exception of type 'System.Exception' occurred in Microsoft.VisualBasic.dll
...and some of other type (but most of them in Microsoft.VisualBasic.dll).I was wondering if this is common in projects converted from VB6, or if it is caused by bad design in our code...
When I try to create a instance of a COM class it throws an exception as Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG))
View 2 RepliesWhen I try to create a instance of a COM class it throws an exception as Class not registered (Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG))
View 4 RepliesI'm trying to catch a user defined permission exception - i.e. a user does something their level of system access won't allow, permission exception is thrown. My problem is, the exception is caught and then rethrown as a genertic System.Exception.Is there any way I can deduce the original exception type, without resorting to string comparisons, like if ex.ToString.Contains("Permission denied"
View 2 RepliesWhen catching an exception in .net, you can have as many type-specific exception blocks as needed. But I usually try to have at least one "general" exception catch block. But is there a way to get the type of the "real" exception thrown that is caught by the generic exception handler, perhaps using reflection?For example, if I have
Catch ex As System.ServiceModel.FaultException(Of InvalidUser)
ProcessModuleLoadException(Me, ex)
Catch ex As System.ServiceModel.FaultException(Of SQLExceptions)
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i have about 20 possible exception messages that i want thrown when an error occurs.i need somthng like this when catching the exception
Try
' do domthing
Catch ex As CustomInvalidArgumentException
'do domthing
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do i have to create a class that inherits from Exception for each type of exception?
I have the following code :
Imports System.Data.OleDb
Private Sub getData()
Dim connStr As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:
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Exception Text : Can-not find installable ISAM.
Is there anyway to create a Custom Exception without inheriting System.Exception?
my reason is that they have a lot of methods which i do not wish my Class to have.
I have written a program which uses a SQL exception class and then use it show custom messages for the primary key violation. Also i want the primary key value that caused the violation. How can i get all the primary keys which generated the exception from the sqlexception object.[code]
View 1 RepliesI am getting below exception when i am going to enter record in a table through StoredProceduer of sqlserver i have a field which i need u update immediately after insert of new record in table. for that i created a sotredprocedure in which i wrote insert command first and after that i wrote a update command for same recored but it gave me below error SQlException: Transaction count after EXECUTE indicates a mismatching number of BEGIN and COMMIT statements. Previous count = 1, current count = 2. Uncommittable transaction is detected at the end of the batch. The transaction is rolled back. Some Error in stored procedure execution
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I am using VB.NET 2005 to create a Windows forms application. I have a procedure named SendMail that creates an instance of Outlook.Application, to send an email from my application. I found the code on this forum, I think.The procedure works fine, but I can't use error handling with it.I call the procedure from a button click event. I put the procedure call in a try/catch block, and the application won't build, with the following error.
Error 68 'Catch' cannot catch type 'Microsoft.Office.Interop.Outlook.Exception' because it is not 'System.Exception' or a class that inherits from 'System.Exception'. C:datadevdmtiQTSQTSv7_1_20100212wQTSQTSReportsCriteria
pt_frmReportViewer.vb 43 21 QTS
Here is the code:
Sub SendMail(ByVal sFile As String)
' Create an Outlook application.
Dim oApp As Outlook._Application
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catch an exception and then throw another exception? Like so:
Try
' Do operation xxx
Catch ex As Exception
' Operation xxx failed, need to execute cleanup
[code]....
The reason for doing this is that while I catch my exception on a higher level logic (to make sure I can log it properly), I need to do some actions in the event of the exception that I can only do inside my class/function.
I'm working on a VB.Net WinForms app. This app shows rows of production lines that the user will go down row by row and print a package of ActiveReports documents. This package can contain up to 9 reports. The package is selected and told to print, it then gets sent directly to the default printer of the machine using ActiveReports' mechanism:
rpt.Document.Print(False, False, True)
These reports also use images pulled in from the file system. When they run through the rows quickly, they sometimes encounter:
A generic error ocurred in GDI+
Then followed by:
Exception of type "System.OutOfMemoryException" was thrown.
This causes some documents to not print and they have to go back and figure out which ones didn't print. I know the machine is not out of memory, so my assumption is that the printer memory is filling up or reports are trying to use the same image when printing and causing an issue there.If it is the printer memory filling up, is there any way to slow down the adding of documents to the print queue, or at least pausing to wait for space?