Call Function - Invalid Attempt To Read When No Data Present
Mar 25, 2009
When I run my application the following code prompts an error. Ideally, I want to populate the TxtOracleNo with a value read from another table on my form based on certain conditions i.e., prac_no, prac_eid and pay_method is the same in both tables then populate the Oracle No on TxtOracleNo text box.
The error given is
"Invalid attempt to read when no data is present"
The function is shown below
Private Sub Oracleview()
'Open the database.
'Delete any existing record
Dim cmd As New SqlCommand
Dim conn As SqlConnection = GetDbConnection()
[Code] .....
I checked that data in the database and it is available in both tables. Probably, the problem is where I call the function. Presently, I call it on loadform.
In a nutshell...I have developed a site in ASP.Net and VB.Net which allows a user to create an order and submit it to a SQL Server backend database.
When the order is placed...an xml file is also produced, showing the items that have been ordered...which is then loaded in to a program to update stock quantities.
The code I have is as follows:
Public Sub butSubmitOrder_Click(sender As Object, e As EventArgs) Handles butSubmitOrder.Click Dim sqlConn As New SqlConnection
I am not sure why this code doesn't work. I have follow according to the table field data and it I am still unable to get the SQL Datareader to work. I have checked the tables and all datafields, everything is correct. But I still am unable to read data from the database.
Dim connectionString = ConfigurationManager.ConnectionStrings("CleanOneConnectionString").ConnectionString Dim myConn As New SqlConnection(connectionString) myConn.Open() Dim cmd = "Select * from [Member] where Email = @Email" Dim myCmd As New SqlCommand(cmd, myConn) [Code] .....
There are already multiple threads about this, but i don't have the knowledge about the different SQL databases/methods to make heads or tales from it.I am using an OleDbDataCommand, an OleDbDataReader and the following code
Dim Query2 As OleDb.OleDbCommand Dim RetVal2 As OleDb.OleDbDataReader Query2 = New OleDb.OleDbCommand("Select [section], [title], [id] From " & DtSections & " Where [volume] = " & volu & " And [chapter] = " & chapter & "", AccessConn)
[code]....
value)In order to evaluate an indexed property, the property must be qualified and the arguments must be explicitly supplied by the user. Type) Object?
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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
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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
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I know it's possible to read from database and generate them onto listbox but how about listview using call function. here's a sample of what how a listbox is able to read from a database and generate them on the listbox.the listbox is reading from database, how does one make it to read from an active listview.
Private Sub frmReceipt_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim strConnection As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source= luggageb.mdb"
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Dim classInstance As New ManagementObject("rootCIMV2", "Win32_NetworkAdapterConfiguration.Index='7'", Nothing) Dim outParams As ManagementBaseObject = classInstance.InvokeMethod("EnableDHCP", Nothing, Nothing)
i have made application in vb.net which access the MFC Regular dll and it works fine if i run application from windows xp but when i run same dll from windows 7, it gives me above error.
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obj.Read(N byte) //--> if no data come within 500ms close the thread
My question is: considering that the Timer_Tick function will be called every (for example) 100ms, How long does the total execution last? Timer_tick time + Thread Timeout (100ms + 500 ms = 600ms) or just the Timer_Tick time (100ms) causing the anticipated thread closure/crash?
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Anyway what I am trying to do in steps:
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ive two custom controls, which are used to draw and edit etc...(like paint but customized....) i want to save their images with a single click....So im using the Getimageofcontrol function to do it....its code is below:::
Public Function GetImageOfControl(ByVal c As Control) As Image Dim rc As New Rectangle(c.PointToScreen(c.Location), c.Size) Dim i As Image = New Bitmap(rc.Width, rc.Height)[code].....
and the code to call this function for saving the images is simply.. ...
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[Code]...
Note: I tried to add the expando property before the parent class does to see if the code would check for its existence and skip it, but that just causes an exception.
