Writing And Reading Simple Structures From Files Into An Array

Dec 23, 2010

I coded anything but I remember when using VB6 or Pascal/Delphi we used to define records/ structures with fixed length fields, then write those structures to a file knowing that they would always be the same length. You could then open a particular record within the file or simply find out how many records existed by reading the file length.From what I understand, it seems that such methods are depreciated in VB.NET and such structures are written as a stream.Does it now mean that we can define things like variable length strings and not need to worry about buffers or boundaries?Is it possible to read through such files and pick out individual records? Are there methods of determining how many records that exist in a file? What I'm looking to do is simply store multiple records of a structure in a file then retrieve them into an array so I can manipulate their order by sorting the array and search within the array. This is only a learning project so it is unlikely that the resultant array is going to be large, although if this is not generaly a good method of doing this then it might be interesting to fidn out what is. So far, I have read that they way to write a structure to a file is to "serialises" it and then write the bytes - is this correct?[code]

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Reading And Writing INI Files

Mar 12, 2011

I'm creating a simple forms application where users can enter their details and save the information to a .ini file because I needed this for a simple game profile. I've tried to make it write "Name =" + txtname.Text but it won't work anymore. And as well as that, I don't think It will load the text back from the ini file.

Here's the code I used;
Public Class Form1
Dim hFile As Long
Dim sFilename As String
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
[Code] .....

Form designer: [URL]
Form1.resk: [URL]
Form1.vb: [URL]

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Writing/Reading .dat Files?

Dec 28, 2009

seeing as '.dat' files contain only what you want them to and there is no preset encryption for them etc could I write data to one by using this simple process:

1) Change file extension to '.txt'
2) Decrypt
3) Write
4) Encrypt
5) Change file extension to '.dat'

and pretty much the same for reading it. or am I thinking to simply?

I thought of the above way as i know how to write to text files already, but is this the best way to do it? or is there a better way?

EDIT: Nevermind you just write to it like a text file and encrypt/decrypt it. request lock/delete from mod.

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Better Ways For Reading And Writing To .txt Files?

Jun 29, 2006

I am trying to create a bunch of records, there will be a limited number of "Codes", about 50. Each "Code" is associated with a name from a textbox, I was trying to have it save each one when you click a button, to a .txt file.So, from the start the record will be blank, the person will go through the form, choose a number from a numerical up and down box, pick a name associated with it (both of these are mandatory and not implied). When they click the button, it will save the contents I talked about into a .txt file, say the number is #2, and the name is "Bob", the next time they try to change that value for #2, it will overwrite "Bob".

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Getting A Code For Reading And Writing To Files?

Jul 18, 2012

I have been given the task of basically reading and writing to and from files. Below is the code from one sub:

If btnSaveRecipe.Enabled = True Then
FileName = "C:UsersLeylaDocumentsRecipe TaskRecipe.txt"
FileWriter = New IO.StreamWriter(FileName)

[code]....

I can't work out what i've done wrong, but when I open the file itself in the folder, it is empty.

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Reading And Writing To Ini Files In VB 2010?

Sep 13, 2010

I am trying to search for snippet for reading and writing ini files in visual basic .net.

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Reading From And Writing To Text Files?

Mar 11, 2010

Input File to read:
SAMPLE NO: 10S-02013
Moisture 10.1

[Code]....

I am not getting the right output I need, as whenever it reads a line, it looses my sample numeber.

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Reading/writing Files VS2008?

Apr 6, 2009

I'm writing a system with several programs, each of which will start off with a number of 'run time parameters' which will be stored in what I call 'personality files'. Each file will have about 10 elements ( file locations, logo files, dates, numbers , text strings ). I"m starting by building little programs which maintain ( build and modify ) the personality files. To begin the first one, I"m only reading/writing 3-4 strings ( I"ll graduate to dates and numbers later )When I run the program below, I get " The process cannot access the file 'c:yyyyyyyy.zzz' because it is being used by another process. ". I also get"A first chance exception of type 'System.IO.IOException' occurred in Microsoft.VisualBasic.dll "

I get these errors even though I've done the usual stuff like deleting other versions of the test file, cancelling other processes which might be involved, and so on.

Code:
'.... user has clicked on SAVE in menustrip ....
Private Sub FileSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles FileSave.Click

[code]....

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Reading/writing Text Files?

Mar 3, 2009

so i have it so that the user input three initials and presses an enter button. Then it goes into a listbox where theusers initials and game score enter. I then have it transfer to a text file. all this works but i need some code toun through the text file and arrange them from highest to lowestheres my current "HighScore" codei know its going to be a for loop but im a beginner in vb and it would be so much easier in java button1 is the enter buttonbutton2 is the save button that saves to a text file

Imports System.IO
Public Class HighScore
Dim objStreamWriter As StreamWriter

[code]......

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Using DAT Files - Reading - Writing And Formatting

Sep 1, 2011

i was wondering does any know of any good tutorial on using dat files eg reading writing and formatting. I am pretty sure you and use stream reader and writer form the IO but what about formatting.

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VS 2010 Reading And Writing Files?

Dec 27, 2010

My app has a series of parameters that is to be stored in an external files. Eventhough the "parameter" file could be edited by the end user, I really don't care that much about what the user does to them.

So my two questions are, what is the most effeicent means of reading and writing a file and in what format should the file be in? When I say effeicent I mean, what utilizes the least amount of memory during the process, is fast, and disposable.

Example: XML, Text, something else. StreamReader / StreamWriter or what ever.

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Reading Writing To External App.config Files?

Aug 28, 2010

I need to read the keys from several external applications .config files, is it possible to specify the file for AppSettingsReader?

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Reading/Writing Files On Networked Comps?

Nov 12, 2009

how I should go about getting the names of the computers on a network. And if the comp had file sharing on, get the "tree" of dirs on the computer. Would I need to authenticate myself in order to read/write actual files to it?

how to even get started, so I don't have any code - the best thing I can think about doing is getting the tree of "\\network" or something. (forgot what it was called)

find some code (or give some search keywords or names of APIs) that would allow me to see and write/create files on a networked comp.

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Text Files Reading Writing Resources

Jul 30, 2009

I am witting an app that will generate batch files to do an unattended installation of a share point 2007 farm. I already have a batch file I use and it's pretty big. I copied and pasted the content into my application, and I'm using the System.IO.StreamWriter to write to the batch file from the winform. [code]As you can probably guess, I'm doing all of this in my mainform code window. There are maybe 3 or 4 batch files that will be generated based on the selections made on the form. For example, I'm generating a batch file to create the OU, Group and service accounts the farm will use in active directory, I'm creating a batch file for all of the variables that will be used for the additional batch files created, etc. How can I split this up? is there a way to create the batch files without having to actually copy, paste my existing batch file content into the mainform code window? I'm using file.writeline on each line of the pasted content by the way.

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UniObjects For .NET - Reading And Writing UniVerse Files

Feb 13, 2010

Our organization is using UniObjects for .NET but the CD seems to have gone missing. I need to figure out how to read and write to and from files in Universe. note the program is written in VB.NET

Dim uniSession As UniSession
Private DATABASE_IDENTIFIER As String = "uvcs"
uniSession = UniObjects.OpenSession(_hostname, _username, _password, _account, DATABASE_IDENTIFIER)

[Code]...

how to insert new values, and read values from the LICENCE_STATUS table.

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VS 2010 Reading/Writing Text Files?

Oct 12, 2011

I have seen a few different ways of Reading/Writing Text files. What i am trying to achieve is a simple debug file in the most efficient way possible. Currently I have....

If System.IO.File.Exists(debugpath) = True Then
Dim Debugwriter As New System.IO.StreamWriter(debugpath, True)
Debugwriter.WriteLine(debugwrite)
Debugwriter.Close()

[code]....

1. Do I have to close and reopen the file each time I want to write to it.

2. In vbscript I would simply open the the file at the start of the script and close at the end is the same possible here.

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Writing To And Reading From Files On Phone Using Com Ports?

Aug 31, 2011

I have this htc evo phone of mine and I know there are programs that can read and write to the phone via com ports, well anyway is there a way to read and write to files on my phone via com ports, I know you can but how? Because the only thing I can do in comports in vb is ComPort1.Write() and ComPort1.Read so how do I navagate through the phone via comports and read a files contents. And write to it.

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Writing Data From Listbox To .txt Then Reading .txt Into An Array?

May 15, 2012

I�m currently working on a school project and I have encountered a problem in my code. When i write the contents of my listbox to a file called stock.txt it seems write an invisible linebreak in-between each data entry, my problem is that when I load my array on the next form those invisible linebreaks causes my array to load the data incorrectly.

I have attached a pic of my stock.txt file

The Code that Edits and writes to stock.txt

Private Sub BtnRemove_Click(sender As System.Object, e As System.EventArgs) Handles BtnRemove.Click
'Removes the selected item from the listbox then updates stock.txt
lbxStock.Items.Remove(lbxStock.Text)[code].....

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Diary Program - Reading, Writing Text Files?

Jan 23, 2012

i have started programming a diary sort of program. i have a home form which takes you to other features. im not sure if there is an easier way to do this but the view is week by week with a new week on a new form. and on each form i have a separate text box for each day. using the code:

'In the form load event:
txtMonday.Text = My.Computer.FileSystem.ReadAllText("DayMonth.txt")
'In the text-changed & form closing event:
My.Computer.FileSystem.WriteAllText("DayMonth.txt",
Monday.Text, False)

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Increase Speed Of Reading And Writing Text Files?

Sep 1, 2009

I have created a code in VB.NET to read data from text files. Data is read from a list of files, where each file is changed using a for loop. Data is written to a new text files. Each file is read one by one and written in the same way. Now, my speed of execution is very slow. I am using a Quadcore processor with only 20-30% of CPU utilization when my code runs. Is there anyway I can increase the speed of reading and writing? To read only 125 files it takes 10 minutes or more, which is very slow indeed, because in the end I need to read thousands of files and write them. Each file is approxiamately 30-50kb.

Here is my code.

Public Sub ReadRMRDataFileIntoTextFiles()
'Read in the customerids once up front
Dim customerids As Collections.Generic.List(Of String)

[Code].....

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VS 2008 Reading Ascii Txt File Into Array And Writing It?

Jan 3, 2010

I'm reading a txt file into an array and then writing a new file one line at a time. The reason i'm using array is that i'm searching for a few lines that i want to find and replace.

However in my file I have some ascii characters but they aren't read well. I read something about System.Text.Encoding.Default but I don't know how to implement it in my code.

[code]...

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VS 2010 Reading/writing 2d String Array From/to File

Sep 7, 2011

I can write a 1-d string array to file with:

Dim test() As String = {1, 2, 3, 4, 5}
File.WriteAllLines("C:MyFile.txt", test)

but can't see how to write a 2-d array to file.

I've tried this:

Dim test(,) As String = {{1, 2, 3, 4, 5}, {34, 22, 12, 33, 55}}
Dim myfile = File.CreateText("C:MyFile.txt")
Dim row, col As Integer

[Code].....

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Saving And Writing Structures?

Jan 29, 2011

The following is a mini version of a data structure that I need to be able to write & save to disk. Can someone give me a sample of code needed to do this

Public CardType
Card(0 to 52) as Integer
Suit(0 to 52) as Integer

[code]....

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File I/O And Registry :: Writing Structures To Disk

Oct 21, 2010

My application uses structures that contain strings and arrays that I want to write to disk. I understand that I can create the fixed length data types in the structures by using "ReDim" and "String$", but my question is: Does VB reallocate the storage for the structure which includes these redimensioned members in-line (which would be necessary in order to write the contents to disk), or does it allocate heap and merely store a pointer in the structure?If only a pointer is provided, is there a straightforward workaround to allow me to create fixed length data types in a structure that could be written to a disk file?Or, Is there an I/O method that will handle the situation by recreating a contiguous buffer containing the structure before writing it to disk?

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[2008] Reading And Writing Files : Open "infile90.txt" For Input As #1

Jul 20, 2009

im not able to find lots of command that i used to use in vb 6 i want to know the syntax for READING THE TEXT FILE and WRITING THE RESULT IN TEXT FILE in vb6 i used the following syntax:: Open "infile90.txt" For Input As #1 this is giving me error...

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Reading And Writing Files On External Hard Drive, Code To Ensure SQL Or Data Read/write Execution In Case Of Periodic Drive Reconnect?

Dec 18, 2010

The drive is connected via USB and the problem I'm having is that, periodically, while my code is executing, the usb drive seems to disconnect and reconnect. (Nothing to do with the program, but the drive itself).I want to find a way to prevent these temporary drive reconnects from interrupting my code. IE, i want to insure that whatever read or write that is requested is actually executed even in the case of a temporary drive interruption.

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Initialising An Array Of Structures

Nov 7, 2009

I have a Structure, and I am having trouble initialising it. Specifically when I try to populate the Vector3 variables, it tells me that they are Nothing, so I need to make them New when the array of this structure is declared.[code]Structures cannot declare a non-shared 'Sub New' with no parameters.I have no parameter to supply, and this will be an array so I'm not even sure how I would supply it.The second option to fix the error is to make the Sub New shared, but then I get other errors: Cannot refer to an instance member of a class from within a shared method or shared member initializer without an explicit instance of the class.Does anyone know how I can resolve this. My end goal is to have an array of this structure type with the Vector3s ready to use.

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Need To Have An Array Of UDTs(Structures)

Feb 21, 2012

I need to have an Array of UDTs(Structures). Elements have to be added (at end) and removed (from anywhere). The different values of the elements need to be changeable.

I know how to implement it as an oldstyle array, but wouldn't it be better to implement as a List ( of T)? and if yes is such a procedure possible?[code...]

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Save An Array Of Structures In .NET?

May 31, 2011

I have 2 Structures

Public Structure One
Public ItemOne As String
Public ItemTwo As Integer
End Structure

[Code]...

Results In an Unhandled exception. Bad Record Length. and then If I close it and reopen it I get an 'Unable to read beyond end of stream' error. So what is the best way to save an array of structures? Binary Reader/Writer? and why does this way not work (Even if its derived from VB6)

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Sort An Array Of Structures In .NET?

Nov 17, 2009

I have an array of structures:
Structure stCar
Dim Name As String

[code].....

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