i 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 RepliesI 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?
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]....
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]....
For 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 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 create a treeview in VB.net, the data has to be loaded from MSAccess 2010 database. When I try to run this program I get error : Argument Null Exception was unhandled, 'column' argument cannot be null and the program crashes. I have pasted the code as under:
Imports System.Data.OleDb
Public Class frmRating
Private Sub frmRating_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles
[code].....
I am trying to create an xml editor that read and write xml. my code reads the xml with no problem and allows me to create new rows but when I try to "write" it over I get the following error: "Token StartElement in state Epilog would result in an invalid XML document"
here is my xml:
<?xml version="1.0" standalone="yes"?>
<MacroList identifier="test">
[code].....
i am trying to find the loctaion of an item in an array but ecah time i run the for each next loop i get a null error. code follows:
[Code]...
I keep getting the "Object reference not set to an instance of an object." error and it tells me to check if the pp(f, 0) object is null .... which I know it is not.[code]...
View 3 RepliesI 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]....
I am getting the attached error when any cell in a row is empty. How to avoid this error and to accept the null values?
View 4 RepliesI using ADO to get som values from a SQL DB one off the fields can have the value NULL And if i use:
txtinfo.Text = RS(
"info").value
Then i get an error.I have try with IS NULL - but that dosn't work
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.
Im trying to write code that will insert 'records' into an xml file, but everytime i click the button to make the changes to the XML file, it throws a null reference exception, ive gone through this code must be 100 times and cannot find what needs to be declared as 'new' as i know nodes can't be 'new' and the doc is 'new'
Imports System.Xml
Public Class frmuseradmin
[code]......
I get the following exception for the code shown below. The error occurs when i request access token.I downloaded the latest dll(2.3.1) from the twitterizer website.
{"Value cannot be null. Parameter name: String"}
Dim OAuthTokens As New OAuthTokens
Dim accessToken As New Twitterizer.OAuthTokenResponse
accessToken = OAuthUtility.GetAccessToken(ConsumerKey, ConsumerSecretkey, "oauth_token", "oauth_verifier")
I 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]...
MVC 3. VB.NET I have the following controller action in my application to send generated PDF files to the User by download. The function works fine when the controller itself has been invoked. But when I call to the function from outside the controller it returns a " Object reference not set to an instance of an object " error as soon as it hits the response.contenttype line. I have verified that all of the variables are in fact making it to the below action.[code]any ideas why this is only working when called explicitly from inside its containing controller???
View 2 RepliesI am building a VB.net application using VB Express 2008 which connects to a MySQL database. Right now, I am only selecting records, but will be writing code for update / insert. I have installed the MySQL Net Connector, most recent stable build. I have set a reference to it in project references. It makes a connection and reads just fine, no issues there at all.
My problem is this: When exiting the project (via calling "End") I am receiving a null Exception error. Here is the error[code]....
My code block is below. As it turns out, rdrCurrentRate.GetString(12) is a null value, but the code block throws an error. "Data is Null. This method or property cannot be called on Null values."My intention is to write "if rdrCurrentRate.GetString(12) is NOT NULL, then sCurrentRateType = rdrCurrentRate.GetString(12)"
What am I missing here?
If Not String.IsNullOrEmpty(rdrCurrentRate.GetString(12)) Then
sCurrentRateType = rdrCurrentRate.GetString(12)
[code].....
I have the following code below which has an error. When the checkbox is set to true and for example change the "role", and click save the following error is given;
"Index was outside the bonds of the array".
I know the reason of the error but don't know the solution..
The TxtPayCont is a concatenation of title, fname, and lname in an array. Therefore, if all the fields have values, then it works fine. So if it is Mr Jones Tim, this works, but, if it is Mr Jones it does not. It has to have 2 spaces to work. Is there anyway round this...
(see code below)..
Code:
i need to pass null value but error dim drf as date
[Code]....
Dim Upd As String ="UPDATE sakit set tanggalsakit'" & drf & "' WHERE orang= '" & id& "'
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 RepliesRun-time error 94 invalid use of Null
View 16 Repliesim 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 testing a program, and I am getting a null reference error at this line. oParent.Invoke(oParent.cUpdatingSolidWorks, iSolidWorksItem). I have stepped through the program, and all the items are created. A watch window with the three objects all have data in them. I am wondering what would cause this error if the objects exist. [Code]
View 5 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 RepliesI have built my project successfully but when I run App. I get error message:value cannot be nullParameter name: activationContext
View 3 Replies