"System.ArgumentException: Invalid Operation. The Connection Is Closed "?
May 19, 2011
I get this error on the server. I cannot replicate this on my development machine.I get it when i call ExecuteReader, ExecuteScalar or when i try to fill a dataset.I use an oracle database.This, i think, increases when the load on the server increases. Im not sure.i need help fixing this. Please let me know if you need anymore details.The code for ExecuteScalar would be as follows
Public Function ExecuteScalar1(ByVal sExecuteString As String, ByVal sConnectString As String) As String
Dim OrclCmd As New OracleCommand
[code].....
View 1 Replies
ADVERTISEMENT
Feb 29, 2012
I have this as my transactions code and I'm having an error connection closed . Iv tried fixing it with odb.open but i dont know where should I put it
[Code]...
View 1 Replies
Oct 20, 2009
I've tried pretty much everything to solve this problem (except what works, obviously) and almost worn out Google, so now I'm giving this forum a chance. Basically I'm making an application which needs to map column names in an excel spreadsheet to fields in a table (TableB) through a data transfer setup table(TableA); To make this work as planned, I need to compare a value in "FromField" in TableA with headers/column names read from an excel spreadsheet into a list of strings, and if they match, map "FromField" against "ToField", prior to importing data from the spreadsheet. The column names that don't match with "FromField" are to populate a combo box in the FromField column in my DataGridView.
PROBLEM: I get this to work fine as long as I don't handle case differences (e.g. "FieldToBeImported" in Field1 vs. "fieldtobeimported" as header in spreadsheet), but this prevents matching words with case differences to be mapped, and leaves it to the user to manually map fields that should have been mapped automatically. However, if I make a ToUPPER copy of the List Of String that contains the MS Excel column names and compare them to a ToUpper version "FromField" data, I get the error message from the topic:
"System.ArgumentException: DataGridViewComboBoxCell value is not valid"A little explanation on DataGridView2 before diving into the code: Column in index 0 is a DataGridViewComboBoxColumn added in code, where matching fields in column 0 and 1 are mapped, and non-matching fields are populated in the combobox.Column in index 1 is "ToField" (TableA as source), Column in index 2 is "FromField" (TableA as source) and is hidden in runtime.
[Code]...
View 2 Replies
May 31, 2011
for example i have this code :
Sub Month()
Dim Conn As New Data.OracleClient.OracleConnection
Conn.Open()
Try
Dim Cmd As New Data.OracleClient.OracleCommand
With Cmd
[Code]...
What will happen to the datareader when the Connection is closed ( Conn.close)
Will the Cursor that is used by the datareader be freed ? or will it stay open ?
If the cursor that is used by the datareader is still open , when will it be automatically closed ? or should i just closed it manually ?
Will it cause the dreaded "ORA-01000: maximum open cursors exceeded" ?
View 3 Replies
Nov 16, 2009
I have the following code running, the first time I change the selected index, everything runs smoothly. However, if I try to change the selected index again, nothing happens and the subcategories combobox values do not change.
Private Sub cboMainCategory_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboMainCategory.SelectedIndexChanged
'* make sure the combobox is fully loaded
[code]....
View 2 Replies
May 6, 2008
I made a program with Visual Basic Express 2008. I got this error message when I try to close my program after running it. (PS: It is a simple code that can login into Microsoft SQL Server)The error message shows the error was caused by the "system.drawing" (Parameter is not valid). Also, I have been trying the code in VBA (Excel). When I tried to close Excel after running my code, I got the same problem (Microsoft Excel has encountered a problem and need to be closed.....) and the error report shows the error was caused by "system.drawing" as well.
View 6 Replies
Aug 3, 2011
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]....
View 2 Replies
Mar 15, 2009
I have a simple scraper. It works on some websites, but on some there is this Error:
Quote:
IOException was unhandled Unable to read data from the transport connection: The connection was closed
It is occuring at "Dim htmlresults As String = Urlcontents.ReadToEnd()".
'Create the HttpWebRequest object
Dim req As HttpWebRequest = WebRequest.Create(URL)
'Set the timeout to 1 second (or 1,000 milliseconds)
req.Timeout = 10000
[code]....
View 2 Replies
Jun 9, 2011
i am getting an error like invalid attempt to read when reader is closed
[Code]...
View 1 Replies
Dec 19, 2011
Try If functionmode = "ADD" Then
[Code]...
View 1 Replies
Jul 5, 2011
I got this error..The connection was not closed. The connection's current state is open.
This is coding to add data in Ms access in vb...
Imports System.Data.OleDb Public Class Form1
[Code]...
View 5 Replies
May 20, 2010
I'm developing a device app in VB.net that will access a SQL Server database. I need to establish a connection when the app is launched, and keep the connection open until the app is closed. I've done the following:In the Master Module:
Public CNN
As SqlConnection
In the Main menu form load:
CNN =
New SqlConnection(sqlConnString)
CNN.Open()
Then when I want to read from the database:
Dim sqlDR
As SqlDataReader
SQL = "SELECT Name FROM Table"
[code]....
When I run the same code without the global CNN, but rather dim the connection inside the Select function, all works well.
View 6 Replies
Mar 11, 2010
I'm trying to insert a new records into database, one of those records is a "datetime"...when I type a wrong date, and try to insert those values into database, i get an error (about wrong typed date etc.)...ok, that's fine, things need to work that way. But here comes the problem, I correct the date, and then try to insert values again...here I get an error from the post title. And this doesn't work until I close that form and run it again...here's part of my code:
Dim cvLicence As New SQL
Try
cvLicence.upis("INSERT INTO blabla (itsnotimportant) VALUES ('something')")
MsgBox("everything's fine", MsgBoxStyle.Information)
[code]....
View 7 Replies
Jun 12, 2011
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
exitwithout()
[code].....
View 1 Replies
Aug 11, 2011
It's System.ArgumentException: An entry with the same key already exists. error.Here is the whole stack trace:An entry with the same key already exists. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.Exception Details: System.ArgumentException: An entry with the same key already exists.
[code]....
View 4 Replies
Jun 5, 2009
I have an error but will explain how i set up my db:Two tables, One is called Area and the other Postal_Code.
The aim is to assign a postal code to the area.Sometimes we add postal codes and sometimes these codes change or need to be deleted.I used the wizard to create the datasets and dropped them on two forms linked to a SQL db.We can Add,Edit,Update & Delete so all is working fine there is no relationship between te tables as they dont need to be linked, I only require the PCode to me added to the Area Table, not any ID or Index etc.
One of the fileds in the Grid on the Areas form is the Postal Code, its set to a combobox that when the user is adding it gives them a selection of postal codes to select from.I get the error when loading the datagrid on the Area form: System.ArgumentException: DatagridViewComboBoxCell value is not valid
This happens only when the postal codes are changed or deleted in the Postal codes table.
I know what causes the error - the dropdown on my Areas form looks for the value in the Postal Code table and does not find it beacause it has either been changed or deleted.Im doing this manually - I go into SQL and remove the postal code data from the record.Then the form loads with no errors.
Q: Is there any way when the Datagridview loads that I can tell it when the PCode does not exsist in the Postal Codes table that it should rather leave it blank and warn the user that there are errors they need to fix befor they can save.
View 1 Replies
Dec 13, 2010
is the insert of my code to close a form and it happens to be that when i click on the close button it gives the error "Operation is not allowed when the object is closed"and highlights the adoPrimaryRS.Close() line.
View 7 Replies
Sep 23, 2009
I am using an ADODB connection to a Sybase ASE Database for a small app that runs queries and returns the results to a grid, to XML and to Schema file. I recently tried the query on a Sybase script (Between a Begin and End statement) and had an exception when I used RS.EOF which reported "Operation is not allowed when the object is closed." The code works fine for other queries, including those between begin and end statements, so I did some debugging and found that the failure only happens when my SQL script (Which is typed into a rich text box) contains either Sybase variables (ex. @MyTable) or uses temp tables (ex. Select * into #mytemptable from myrealtable). The actual execution works OK (without an exception) but the recordset seems to be closed. A failing example is :
Begin
Declare @Name Varchar(30)
Select @Name = "MY_TABLE"
[Code]....
View 11 Replies
Oct 12, 2009
why is the datareader closed? I had to change this from a stored procedure to dynamic because our IT guy was encountering trouble changing the sp permissions.. so there's definitely a time factor
Dim cmd3 As New SqlCommand
cmd3.Connection = connect
Dim dr2 As SqlDataReader
[Code]....
View 3 Replies
Jul 14, 2011
I am not sure if this is how things are supposed to be, but during development, I might like to change a line of code in a nice little helper class.This throws numerousA first chance exception of type 'System.ArgumentException' occurred in mscorlib.dllThe site restarts and I have to navigate back to where I was to see if the change worked.It is massively time consuming, and I hope there must be some option to prevent this. Is there?
View 2 Replies
May 10, 2012
I'm having difficulty using this code that the tutor has provided for me and have a strange error that only I appear to have. Below is a picture and my code... I have double checked my connection and reference and it all seems to be working fine. Whenever I click on a button within my application when i compile it the error below occurs.[code]...
View 1 Replies
May 10, 2012
Essentially every time I run my form it tells me that the operation is not allowed when the object is closed and it points towards my recordset. Below is my code in full (given to me by a teacher! not my own) and I wondered if you could tell me what the problem is. As I understand it there is another option to ADODB which is more appropriate for .net.
Code:
Option Compare Text
Public Class Form1
Private m_cnADOConnection As New ADODB.Connection
[Code]....
View 1 Replies
Jul 14, 2010
i have this error when executing "Operation is not allowed when the object is closed" on line rs = cn.Execute(Query)
this is my
Do
tsReadLine = tsR.ReadLine
If Len(tsReadLine) = 0 Then GoTo skip_line
[Code]....
View 9 Replies
Dec 23, 2011
I am gettting the following 2 errors:
Invalid attempt to call Read when reader is closed and sometimes Invalid attempt to call MetaData when reader is closed when attempting to read from a sqldatareader object. What I want is to list groups in listview. The last column is "Total Numbers".[code]...
It works ok for the first row but after that the first error generates. I don't want to include the COUNT function in the main sql cos then i would be required to group the rest fields (there are 9 of them totally). I tried MARS but it don't work at all in my connection which is like
View 1 Replies
Mar 31, 2011
"Invalid attempt to call Read when reader is closed." is returned when trying to use a SqlDataReader in a Thread or BackgroundWorker (Do While z.rdr.Read() in the bold sections - I know this code does the same thing twice....). I have looked at a few forum posts but I did not find a method to keep the SqlDataReader open when passing the arguments. How do I thread the SqlDataReader loop?
[Code]...
View 3 Replies
Nov 2, 2011
i am developing a windowsService called MyFirstWindowsService. And also i created a setup project for my windows sercive.it installed successfully. But i am unable to start. While starting it shows error like "An unhandled Exception (System.ArgumentException) occured in myFirstWindowsService.exe"
specificaly it tells invalid path "H:".
filestream.Close()
[code]....
View 1 Replies
Feb 28, 2010
In this screen I want to let the user decide which elements are on shown on a label. When I hit the update button (BDUpdate_Click; see below), it first checks whether the Barcode sample text is empty. Afterwards I want to invole the refresh of the label preview. The strange thing is that the first time it works fine, but when I alter the sample text and hit the button again, I get the Error "System.ArgumentException was unhandled. Parameter is not valid." The error points to the DrawSting function in the LabelPreview_Paint Sub
Dim BarcodeLabelUpdate As Boolean
Private Sub BDUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BDUpdate.Click
If BDBarcodeSample.Text = "" Then
MsgBox("Please enter a sample text", MsgBoxStyle.Information Or MsgBoxStyle.OkOnly, ProgramTitle)
[code]....
View 2 Replies
May 9, 2011
I am getting below error, when passing the path which has space between the folder name.
"System.ArgumentException: Illegal characters in path"
I have declared the the path in the variable like below:
Dim sFilename As String = "C:\Test\Windows Service\Schedule.xml"
or I have tried like this as well but same error I am getting.
Dim sSFilename As String = """C:\Test\Windows Service\Schedule.xml"""
and passing this file name to the below code:
Dim docDataSet As New DataSet
Dim docReader As New XmlDocument
Dim xnl As XmlNodeList
[code]....
View 1 Replies
Jul 7, 2010
I'm very beginner in vb. I need to connect two forms with ms access. First form is connect with second using(form2.show). My need is when I execute the coding. I got a error on first form " An error occurred creating the form. See Exception.InnerException for details. The error is: Operation is not allowed when the object is closed.
View 2 Replies
Jan 19, 2011
I'm developing an app in vb.net (visual studio 2008). I have a Teradata back-end that will be supporting multiple users in a production environment. I need to use variables in the connection string as the user/pass will be changed every 3 months.
For the gist of the application:
In it's most basic form - I have a search form which works correctly - it pulls results into a listbox and the user then double clicks the list box which will then open a form that is bound via table adapter to the back-end table (Teradata). My connection string is fine everywhere in the application. My problem is using a modified connection string for the "fill" function of the table adapter once the form is opened.
I'm using the code below for the on-load event and keep getting an "invalid connection string" - again, the connection string works fine everywhere else in the app, and the variables etc... are working correctly.
Private Sub adaptertest_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim DBConnStr As String = "Provider=TDOLEDB;Data Source=TDDEV;Persist Security
[Code].....
View 5 Replies