I am trying to Read a text file from vb.net and then write it to microsoft access. The following is the codes that i have written for this project.
However, there are errors stated:
1. error in inserting record
2. Warning 1 Variable 'DoCmd' is used before it has been assigned a value. A null reference exception could result at runtime. C:Documents and Settings�74958XDesktop6jun[updated]6junForm1.vb 63 9 6jun[code]....
What i've written opens an Access database and one can read and write into it (on a table called Journal)It does indeed work for newly made Access files. However it doesnt work with a specific Microsoft Access database (again .mdb) which was made with a very old Access, like Access 2000 or something.The error message is: Syntax error in INSERT INTO statement.Inside the zipped file below you will find the source code of the program, along with an access file that the program CAN read, and the one access file that i NEED the program to reed but it cannot!
To see what i mean run the program one, try to add a new line to the database. you get an error!now rename the Journal.mdb to "journal.bak.mdb. And the journal_working.mdb to Journal.mdb try to add a new line to the database again without altering the source code at all. it succeeds now!!
NOTE: the program can READ data from both files. but it CANT write data to the old access file
this is the code:
Dim cb As New OleDb.OleDbCommandBuilder(da)
Dim dsNewRow As DataRow
dsNewRow = ds.Tables("AddressBook").NewRow()
dsNewRow.Item(1) = txtFirstName.Text 'or .Item(1) =
[code]....
I am writing an app in VB2010. My code parses a text file, assigns data to variables My??, and then attempts to store this data in an access 2010 (actually access 2007 format) table. Yet, whenever my code gets to MyRow.Item("Artist") = MyArtist I get an error 5 'Artist' does not belong to Table MyTable, but the field/column does exist in the table as do all the others.
01Dim tbl As DataTable = New DataTable(MyTable)
02tbl.Rows.Add()
03Dim lastRow As Integer = tbl.Rows.Count - 1
[Code].....
[code]i want to write Delta_r(i) in access data and then i want to connect that file to Crystal report for plotting.
View 4 RepliesI am having trouble writing information to a 2007 access database. I just want to write a numeric value into a data base. My table name is KW and my field is also referred to as Kw.
Dim theOleDbConnection As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;" & _
"Data Source=C:\Documents and Settings\HP_Administrator\My Documents\value.accdb")
Dim theOleDbCommand As New OleDbCommand("INSERT INTO[KW] (Kw)VALUES (@P1)")
theOleDbCommand.Connection = theOleDbConnection
[code]....
im having an issue writing to an access database via vb.net 2008 i can read form it but not write?
View 4 RepliesAt my company we build a lot of small, administrative type databases generally used by a dozen or less users. We have thus far done them entirely in Access. I've been doing VB forever and would like to write nicer, rich UI apps using a VB front-end to and Access database instead, as I find Access apps clumsy to use; VB apps look better and have more UI options.
I've started to play around with building Data Sources, Binding Sources, etc. and dropping them on forms, trying to create something useful with as little code as possible. I'm just wondering what folks generally think of using this approach. Remember this is for small, not complicated db apps with few users.
I know in the VB6 world bound controls took some heat for being not worth the effort it saved you.Also, is there a good book on the subject that concentrates on creating VB/Access apps with minimal code?
I have searched all over the forums and not found an answer to my question. My question is how do i write to an access database at runtime. The database is also created at runtime. I have a dataset loaded with a table that i needs to be written to the database. how would i write each row of my dataset to my database? Sorry if this sounds a little jumbled together it is late and i am tired. If it is unclear you can ask me and i will answer any questions you have about my question.
View 14 RepliesI have limited experience with Visual Studio and have a question about Querying an Access database. I have created a Visual Studio application that displays and modifies an access database. I have use datagridview and detailed view to insert data and view data in the Access database. I am now trying to figure out the best way to query the data in the database. I have tried right clicking a table in the database explorer and creating a new query. Everything works and I can view the data but I am unsure how to display this query result in datagridview. So my question is how do I view this result in datagrid view?
View 9 RepliesI use Visual Basic in Access, and I have no problem writing data directly to a cell in a database table. But I can not figure out how to write the code for Visual Basic 2008. For example I would
use Me![cust_Cost] = 20 to input 20 in the database table.
I have purchased two different Books on Visual Basic 2008 and not one of them show how to input data manually.
I have written a program to track the membership of a local gym that works perfectly on every computer EXCEPT the computer at the gym. I am pulling out my hair trying to figure out what the difference is any why ONLY that machine throws an error.
Background: The program is written in VB.NET (2008) and calls a MS Access db (PROVIDER=Microsoft.Jet.OLEDB.4.0;). The computer in question is a Vista machine that is extremely slow (I think it's a Celeron with 512 RAM).
History: I have tested the exe on a Windows 7 machine in 32bit and 64bit. Tested on a 2000 and 2003 server with 32bit and 64 bit processors. Testes on a Mac running parallels with XP. Tested on machines with Office XP, 2003, 2007 and machines without Office (thinking it was a resource that was missing) Every machine works but the Vista machine.
The error occurs when the program is trying to update an existing table with a new value that is valid. The field is set to text so I know it's not a casting problem. The error message is a general exception that reveals no information. I can continue from the error but it does not complete the change to the db.
One other interesting note is that the database is accessed across the network so multiple people can use the program at the same time. Unfortunately the Vista machine is the "server" and is the home for the db. The other machines are laptops and are not always accessible on the network. If the program and db are local to the laptops then the program works perfectly. If the db is accessed across the network and the program is local to the laptop then the program crashes.
I try to write some data in a ini file. i can do that first time but second i give me an error[code]...
View 12 RepliesI had one semester of vb.net in college and it was lacking at best. I am trying to write a few lines to a file on my desktop. When i implement the program it will actually find a file in a network share but the concept should be the same. I am basically writing a program to combine multiple csv files into a single file. I have the entire program written except combining the files. this is my code so far. it's incomplete but after i can figure this issue out the rest should be pretty easy. i will later on add parameters and all that fun stuff.
Public Sub writeFirstLine()
fileWriter = New System.IO.StreamWriter("cusersmyusernamedesktopforktruckfile.csv") 'the error happens at this line
[Code]....
I have a file already on my desktop with this name. in the actual program i will have to create it or delete it and all that fun stuff but for simplicity at the moment i just need to find the file.
at the moment it gives me an error that says directory not found. it seems to be looking for a file in the project folder instead of on my desktop. how can i get it to look at my computer instead of the file the project is held in?
I want my program to be able to edit a values within a registry key that resides in 'HKEY_LOCAL_MACHINE'
My.Computer.Registry.SetValue("HKEY_LOCAL_MACHINESOFTWAREXYZ", "MyValue", "MyData")
The above works fine in Windows XP, but throws an UnauthorizedAccessException in Vista.
I'm running Windows Vista with admin privilege and UAC is disabled but still unable to write to windows registry!
My.Computer.Registry.SetValue _
("HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun", _
"Test", "C:Test.exe", Microsoft.Win32.RegistryValueKind.String)
I'm getting error "Unauthorized Access Exception was unhandled."
"Access to the registry key 'HKEY_LOCAL_MACHINE....' is denied."
I've googled the net and found that registry permission elevation is required for admin tasks, Is there away to take registry key ownership through VB.Net code??
I am creating a form which has the customer information entered by the user.When the user clicks submit the row need to be inserted into table "customer".writing the code to connect to the access database and insert the new row?
View 3 RepliesI am getting an error message when I am attempting to write to an excel worksheet using VB.net 2005
Operation must use an updateable query I have gone thru the S/O search results[URL]..My code is:
[Code]...
Application log file have been created to monitor the process and following code has been used to write the log information into text file. For the first time there is no error encountered when the application runs for hours, may be 3 hours i am getting following error "An unhandled exception of type 'System.StackOverflowException' occurred in mscorlib.dll" [code]...
View 10 RepliesI am trying to create a countdown to a date that the user can enter. I think I got most of the code in the button that saves the date. It gets the date the user entered in comboboxes, creates a txt file, then writes all the information to that txt file. I tested it out, but it didn't work. It created the file, but when it tried to write to it, it errored. The error says "The process cannot access the file 'C:Countdown.txt' because it is being used by another process." This is the code.
Dim enteredmonth As String = monthcb.SelectedItem
Dim enteredday As String = daycb.SelectedItem
Dim enteredyear As String = yearcb.SelectedItem
[Code]....
Just completed a program, and tested it. It works, and does exactly what its supposed to do, but I continue to get this error: Cannot Write to a closed TextWriter.The code I'm using is below, but the issue here which I'm guessing would be that in my If statement.[code]'Goes on to create a bunch of tabled XML text.I have this code copied throughout each If Then loop. Basically If the text box is blank then the program will close the table and stop writing.I know the problem most probably lies in that its reading that its trying to close the table or stop writing, but the program forces it to continue.
View 9 Replies"An unhandled exception of type 'System.StackOverflowException' occurred in mscorlib.dll" when writing to registryI write to the registry quite often in my program (Around 10 times every 12 seconds) the error doesnt constantly pop up sometimes it can save 20times and on 21st ill get the above error. How can i fix this. Is it because im saving so often?
View 8 RepliesHow can I change the delimiter when writing my Access table to a text file? I was hoping it would be as easy as adding a similar option like we do for HDR=No; maybe Delimiter=|
Dim AccessConn As New System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=|DataDirectory|mydatabase.mdb")
AccessConn.Open()Dim AccessCommand As New System.Data.OleDb.OleDbCommand("SELECT * INTO[Text;HDR=No;DATABASE=" & userPath & "].[" & fileName & "] FROM tblMyTable", AccessConn)
AccessCommand.ExecuteNonQuery()
AccessConn.Close()
I've been doing some more experiments and have summarized the query as below: I've created the simplest application. A project with a plain form, which writes text file within its application directory. Simple as that.Supposing this was my application which I want to distribute on the world web. I've created a basic installer for this using NSIS installer. The Installer installs my application in a folder created inside Program Files. The OS is Windows7 and UAC is enabled.Now I know many people have been facing difficulties in accessing files inside the Program Files folder. My app is simply creating a plain text file, nothing more, and within its own application directory. It is giving Access Denied error. But if I right-click on the EXE and run it as Administrator, then it works ok.The only solution thats available is not to write in the application folder, and write text file in some other folder which is not protected. My question is that other programs that are installed on my system are also doing it. I have a temperature monitoring software called SpeedFan on my system, it creates log files within its app directory. All other softwares create log files within their app directories, why cant I?I just have to make a small log file for my application and Win7+UAC is not letting me do it. I don't want to write the small file in any other folder. How are the other softwares accomplishing this ?
View 5 RepliesMy application creates a file by writing to System.AppDomain.CurrentDomain.BaseDirectory() & "data/" & filename...Now this works fine usually, but I just added a setup utility to the app, so now it installs to the program files directory. It installs correctly and creates the data folder, however when it tries to write the file it gets an exception "unauthorized access".
View 3 Repliesi am trying to append text to a file. I have tried streamWriter, fileStream, file.writealltext, file.appendalltext every single time i get an error "Object reference not set to an instance of an object" the path is correct and when i use file.exists it says it exists?
View 2 RepliesFor testing purposes, I write a lot of alerts and error messages into a .txt file (some 15 entries per second). At the end of the day, the txt file becomes very large. I am now getting confronted with data loss in my application (threads indicated as being busy). Could it be that my entries in the Log.txt are slowing down my application to the point that the latter becomes unstable ?
View 2 RepliesI have create a vb.net app that creates an excel spreadsheet. When I deployed the app, to the shared drive, I have no problems but the user gets the below error. The user can create the spreadsheet but gets the error when writing. When the user logs onto my PC, the user does not get the error. When I log onto the users PC, I got the error. Application attempted to perform an operation not allowed by the security policy To grant the application the required permission, cintact your local system adminsitrator, or use the Microsoft .net framework
request for the permission type 'System.security.permissions.securitypermissions mscorlib
version 2.0.0.0 culture =neutral
Publickeytoken='b77a5c56193e089'
I have tried to use caspol but it doesn't help?
I have written the following Sub in moduleFunctions to call in any form. But it gives an error: "Name 'txtVNO' is not declared" & "Name 'txtVNM' is not declared"
Public Sub txt_Clear()
txtVNO.Text = ""
txtVNM.Text = ""
End Sub
I use the following code to write to a Foxpro DBF. The SQL table I am reading from has 9500 rows. When I loop through the following code, I get an error after about 940 rows. There is nothing wrong with the SQL data. The message I get is 'Variable Q940P65 is not found'
Public g_OLEDB_ConnectionString As String = "Provider=vfpoledb;Data Source=N:;Collating Sequence=machine;"
dim strSQL as string = "INSERT INTO STATEUSR(DATEFIELD, STATECODE, MINAMOUNT) VALUES(?,?,?)"
[Code]....
I am trying to make a program in Visual Basic 2008 Express edition which have a textbox where the user can write information to search for in a simple database stored in the program-code.
What I would like is that when the user types a word, a string variable connected to that textbox.text will be treated as a string. BUT if the user types a number in the textbox, the textbox.text will be treated as an integer (for example a "Double")