.net Datareader Already Open Error When Not Used Before
Jun 22, 2011
I have this sub as part of my login / logout system. When this sub is called to login users it works perfectly, but on logout it throws an error that doesn't make any sense to me.
[Code]...
This sets a nonsense email address so that when validate_session searches for a valid email/session combo in the db it trips the destruction of the sensitive session data.
The question boils down to this: Why is the error being thrown when the logout sub calls validate_session?
I have two datareaders: [Code] When i'm running the code i get this error in the highlighted line: "There is already an open DataReader associated with this Command which must be closed first." I used different variables in both readers, why do i get this error? do i have to open a new sqlConnection for this task?
I get the following message "There is already an open DataReader associated with this Command which must be closed first." Is the insert statement the most effiecient way to write to the table row by row?
Dim comment As String Dim cnx As Data.SqlClient.SqlConnection = SqlCnx.SourceDB Dim cmd As New Data.SqlClient.SqlCommand("select number,comment from [Comments]", cnx) Dim daComments As New SqlClient.SqlDataAdapter Dim bsComments As New BindingSource cmd.CommandTimeout = "360" cmd.CommandType = CommandType.Text cnx.Open()
I have a problem with my project. here is the problem:
My code for login is as follows:
dim conn as SqlConnection = New SqlConnection("Data Source.................) dim cmd as SqlCommand = New SqlCommand("Loguser",conn) cmd.CammandType = CommandType.StoredProcedure
[CODE]...
Now the error i get is that "there is a datareader associate with this connection that need to be closed"
and in class that starts new thread started every time users change some data(very often)
[Code]...
1. other parts of application are targeting other SQL server...just this adapter is updating only one row(table has two columns, some id and last time any of users changed something.
This reader is done in the form load event and is the very first thing done so I don't understand why it's telling me there is an open DataReader. I've also set MARS=True in my connection string so obviously it is something else.Here's my code and like I said the routine is called at the top of the form load event. The error occurs on the
I'm trying to put together a quick example for another thread about treeviews, and I'm getting a problem when I have a recursive routine, getting the message.
Quote:
There is already an open DataReader associated with this Command which must be closed first.
I'm a tad confused as I am explicitly creating a new command every time through the loop, so I'm not sure (unless its something ADO is doing behind the scenes) how the datareaders higher up the tree are interfering.
Here's my code :
Private Sub SetupChildren(ByVal ParentID As Integer, ByRef ParentNode As TreeNode) Dim MyCommand As New SqlCommand("SELECT * FROM Groups WHERE ParentGroup=@ParentGroup", m_myConnection)
[Code]...
Obviously I could close the data reader down before calling the next level of recursion but it would prevent the code continuing the loop at the current level when it had finished processing children.
I am using a DataReader to get data from a database. For some reason, I keep getting this error "Arithmetic operation resulted in an overflow." The error occurs on the line: courseID = (dr.Item("courseId"))
im getting error when im trying to view a report from my vb2010. value cannot be null. parameter name: dataReader the following is the screenshot for my error and the codes:
[code]I am facing difficulty in coding when intRow loop for the 2nd round. Error message "There is already an open DataReader associated with this Command which must be closed " appear in the above red highlight vb.net code.
I'm writing an application that imports and tidy up address data into a cleaned, deduped excel workbook ordered in rows with each column as an address field. One of the issues I've ran into is that we sometimes get a workbook where the multiple address fields are held in a single cell with line breaks. I've written code to extract all of this data out of the excel sheet in to a dataset with each sheet as a table and the address fields contained within. I now want to create a new Excel workbook from this data with the address fields in Row and columns the problem I have is I can Open/create the Workbook but when I try to insert a new Sheet (Table) I get an error saying the Workbook is read only....
Private Sub MakeSimpleXL(ByRef DsTemp As DataSet) Dim dsTable As Data.DataTable Dim tblName As String Dim dsRow As Data.DataRow
[CODE]...
Here is the error: System.Data.Odbc.OdbcException: ERROR [42000] [Microsoft][ODBC Excel Driver] Cannot modify the design of table '3 _ 10$'. It is in a read-only database. at System.Data.Odbc.OdbcConnection.HandleError(OdbcHandle hrHandle, RetCode retcode) at System.Data.Odbc.OdbcCommand.ExecuteReaderObject(CommandBehavior behavior, String
[CODE]...
It looks to me like it is trying to create the table (Sheet) but has the workbook opened as read only....
I am a newbie and am trying to open a table in SQL Server 2008 table from Visual Basic using ADO and its throwing up a weird fatal error. The error message is:'A fatal error has occurred and debugging needs to be terminated. For more details, see the Microsoft Help and Support web site. HRESULT = 0x80131c08. ErrorCode: 0x0' The code I am running at the time is:
We have developed one multi threaded application in vb.net and we are using Microsoft Access Jet engine 4.0 for database. And when i run the application it execute successfully but after some time it gave an error "Can not open any more table." We searched a lot and we found that we have to close all the connections and all the readers
I have this problem says that "the portName cannot be set while the port is open". When this errors occurred, my application on sending sms could not work. Before I edit the application can work but after making some changes and ask help in this forum, the application does not work and gives errors and it says "the portName cannot be set while the port is open".
I am trying to build a word add in to add xml files to documents, I am under the assumption that Microsoft.Office.Interop.Word.Application.ActiveDocument will work with the document being used, but when I try to use the add in I receive the error: "this command is not available because no document is open " o:
Dim activeDoc As New Microsoft.Office.Interop.Word.Application Dim currentDoc As Microsoft.Office.Interop.Word.Document = activeDoc.ActiveDocument()
When i run my program and try to click on of the button that open anotehr from it says
An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object.[code]....
I'm trying to insert data into a mysql database, I'm using xampp as well if thats of any relevance? I keep getting this error: Connection must be valid and open.
on cmd.ExecuteNonQuery()
I'm following my Microsoft Access application that I've also written as a reference and that works perfectly.' This is the code for inserting into an access database which works and is tryed and tested:
Imports System.Data.OleDb Public Class frmEnterDetails 'text box variables
While trying to open a form I get the following error: An error occurred creating the form. See Exception.InnerException for details. The error is: Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index
Previously the form loaded flawlessly. I made several small changes to subs contained in the form, and after that the problem appeared. These changes included some changes in the constructor. I've tried to track down the problem simply by adding message boxes near potential problem areas, and it seems that the exception is thrown before the constructor is even run. The error message baffles me, since I'm not knowingly using any parameters, and the routine opening the form doesn't refer to any arrays (or any other variables).
Here is the part of the source code that the error message refers to: Private Sub SugNewTagsBtn_Click(ByVal sender As System.Object, ByVal As System.EventArgs) Handles SugNewTagsBtn.Click SugNewTagsForm.Show() End Sub
AM installing visual studion 2010 beta 1, and got the following?
[04/09/12,13:35:30] Microsoft Visual Studio 2010 Professional Beta 1 - ENU: [2] ERROR:Error 25541.Failed to open XML file C:WINDOWSMicrosoft.NETFrameworkv4.0.20506CONFIGmachine.config, system error: -2147024786 [04/09/12,13:35:31] Microsoft Visual Studio 2010 Professional Beta 1 - ENU: [2] ACTION FAILURE:Action ended 13:35:31: InstallFinalize. Return value 3.See MSI log for details.
I'm getting this error message when I try and run my program:
[Code]....
I have run this program man times before. I just added a Windows Form InputCrossForm.vb to my project. When I dbl click on the error message I get a message box title bar "Microsoft Visual Basic 2010 Express" with message "The definition of the object is hidden." Not sure what this means nor what to do to fix it.
I'm trying to open an .exe file via vb code using this method: [Code] But I get the following error message: "Cannot open the configuration file patch.cfg", How can I get round this? Do I need to concurrently open the exe and cfg file? If so, how?
