Here is my code for reading a Binary file:
Dim fs As New FileStream(filepath, FileMode.Open)
Dim str As String = ""
For d As Integer = 0 To l - 1
Dim byt As String = Hex(fs.ReadByte()).ToUpper
fs.Position = d
str+= byt
Next
str becomes:
20202CB962AC5975B964B7152D234B
But when I open the file in a HEX editor, it's:
202CB962AC59075B964B07152D234B70
Why are the 2 different?
I need to write data to a file, preferably in binary format, but I am unaccustomed with the concept. Where's the easiest place to get the basics? I could come here with a specific need, but I'm at the point right now where I am more willing to work within the confines of keeping it simple.
Here's what I know:
1. how to open a new file
2. how to specify the record length
3. how to close the file
Some specific questions:
Does the record length have to be constant throughout the file?
Can I read the nth record without reading the whole file?
few weeks ago i heard my teacher say that it is possible to view any file as a binary array (1s and 0s). if this is possible to do in visual basic please let me know how. Also how would i go about writing an array of binary to a file? For example 01100001 in a .txt file would produce "a"
View 4 RepliesI am fairly new to vb.net but was programming a long ime with vb6 I have a binary file that is a mixture of numbers (integers and doubles) and strings, such as "Programming with VB". I read the numbers using the BinaryStreamReader.ReadInt32 and BinaryStreamReader.ReadDouble, which are no problem
View 5 RepliesI am doing some exercises on encrypting data. One of them are binary files. I am currently using triple DES to encrypt and decrypt the files both in VB.NET and C#... Now the thing is, once it is decrypted in VB.NET and saved, I can execute it again... But for some reason, my C# file is bigger! 20,4K where VB.NET one is 19,0. The C# file also is rendered unexecutable...Upon a closer look. The files appear almost exactly the same, but C# seems to add in a few extra bytes here and there in (seemingly) random places... I am currently using:
File.ReadAllText(String filepath, Encoding encoding); with UTF-8 encoding.
I'm new to VB and trying to figure out how I can replace a bit of descriptive text in a binary file. I presume its binary as I cant open it with anything but a hex editor. I've changed the text (file description) in the hex editor and saved it fine but I'm unsure how I go about saving just the section of information I need. I can work out the saving bit later.In the attached file you'll see the highlighted bit I want to edit. I need to replace the whole line or the file corrupt but I can fill it up with null characters and the numbers are just
View 3 RepliesReading binary file from hard drive in VB and writing to database.
View 3 RepliesI am attempting to read a series of double prcision float values (x,y,z coordinates) from a binary file using the binary reader. Everything works fine except that when I read the number back it is different then the number that was written there (original file is generated by mining application).
written number : 78897.6476586
file contents hex : 40 F3 43 1A 5C CF 43 A4 this converts back to the same number as written using a IEE 754 conversion program. VB returned value : -5.45100266729248E-134 using .readDouble()
I have tried to step thru the file in one byte steps to make sure that I have the proper start position but that did not help any.
I must search a binary string for a pattern. This worked fine in VB6 using Get to read a file into a string and using InStr to search for the pattern. The conversion from VB6 to VB.NET changed Get to FileGet and warned of new behavior, but I don't see anything in the FileGet documentation about not being able to read 0 value bytes.
I don't mind at all changing to a new method, but ultimately I must get the data into a string rather than an array.
[Code]...
I have this code, to read image (saved as varbinary(max) in database):
Private Sub ReadImage()
Dim connection As New SqlConnection(strConnectionString)
Dim command As New SqlCommand("SELECT [Image] FROM z1 WHERE x=1 AND y=1", connection)
[code]....
But it isn't very convenient code. It reads bytes from table, save them to file, and finally open file as image.How can I read it directly to image, without saving as file?
I have a binary converter I am attempting to build and want to read and convert the InputTextBox(alphabetical characters) letter by letter however all I have so far is one letter at a time
Image here is the code I have so far:
Code:
Public Class ConverterForm
Private Sub OpenToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenToolStripMenuItem.Click
[Code]....
i am trying to read data from a sql 2000 database.one of the fields is defined as datatype:image, Length:16.when I am in SQL management studio and do a select for this one column.[code]when i do a datalength on this field it come up with 2404/My question is, I know this is a numeric field, how do i read this into a vb app and how do I break this down into individual values?
View 2 RepliesI have Visual Studio 2008 SP1 installed and lately it is taking longer and longer to bring up a Resource File (.resx) in its standard editor. Some of the file loads up, but you can see that the screen does not paint/render it 100%.I tried doing some searching on the web and the only thing I came across was doing a edit to the GDIProcessHandleQuota registry entry from 10,000 to 20,000. This appeared to work initially, but the problem came back the next day.I am doing an extensive localization project and this is severely limiting the amount of work I get done.
View 2 RepliesI'm amazed at this situation. In QBasic, you could just easily GET and PUT whatever you wanted at the exact position in the file that you wanted. Now in Visual Basic 2008 I'm just completely stumped.
I can't use FilePut or FilePutObject because of a twisted issue. It adds a couple of bytes to describe the length of the data being written: what's the point of BINARY read/write if it won't allow you to write EXACTLY what you want and nothing less or more? There's a way to turn off this issue, and that's by setting the parameter StringisFixedLength to TRUE, but that's where the twisted part comes in. You can't do that. As far as I can tell you have to redefine the function using SUB, for example:
[Code]...
My.Computer.FileSystem.WriteAllBytes. To my amazed surprise, this function doesn't even bother to include the possibility that I might want to put the data in a specific position within the file! I can't believe this. You can either specify to APPEND at the end or not, in the latter case apparently resulting in a write to the beginning of the file. No option at all to specify where in the file you want to put the data. I can't believe this.
How do you write to a SPECIFIC position in a binary file in VB 2008, and do it without the program deciding to add a few "informative" bytes to your data before it's written (totally undermining the whole point of binary files)?
I ran across my first unicode data, and I am not sure what to do with it. I read the unicode text from a binary file using the ReadBytes method, because ReadChars threw an exception when it tried it. Well, long story short, I have found a way to work with the data, I can convert it using a small Function I wrote, which goes something like this: [Code] And this works wonderfully. It just throws away anything not in the ASCII range, including the BOM at the start of the unicode data.
But I would guess that this method is not very universal and probably not the best way. Are there any VB functions available to do this sort of thing? I was able to find something called Text.Encoding, but there didn't seem to be a reverse of that not that I found anyhow. Any ideas?
I'm trying to read back a string that I wrote into a binary file, but it's giving me problems and I don't know what's going on. I open and read my file using the code below:
ifstream input([filePath UTF8String], ios::in | ios::binary);
int numStringBytes;
input.read((char*)&numStringBytes, 4);
[Code]....
I'm trying to read back a string that I wrote into a binary file, but it's giving me problems and I don't know what's going on. I open and read my file using the code below:
ifstream input([filePath UTF8String], ios::in | ios::binary);
int numStringBytes;
input.read((char*)&numStringBytes, 4);
[code]....
There is a lot more to the file reading code, but it's proprietary and this is the part that keeps crashing. It runs fine loading the first two files, but when I try to open a third file, it crashes with EXC_BAD_ACCESS at the input.read((char*)names, numStringBytes); line. I don't see any reason that this should crash. I'm writing the binary files in VB.NET using the below code:
Dim myFS As New FileStream(savePath, FileMode.Create)
Dim encoding As New System.Text.UTF8Encoding()
Dim stringBytes() As Byte = encoding.GetBytes("++string")
[code]....
I have a form.vb file that has recently became a binary file, instead of text file. That means that I can't compare or merge it anymore. When I try so, I get error message that tells me that the file contains 00' character, but I can't find this character although I searched the whole file
View 1 RepliesI'm new to Visual Basic. I'm trying to get this code to read a .txt file line by line. If the only thing that the line says is "B" it should add one to the intTotalBoys integer and so on with G for Girls, F for Fathers, and M for Mothers. I'm not sure why it won't work. [code]
View 4 RepliesI need to read in each line of a file that is comma delimited and I know how to do this.ut for this file, some of the values have quotes around them that contain commas and others do not. For example, the name field has "Doe, John and Lisa" and the other fields do not. How will this be handled? Will it read that whole field in as one or will it still seperate it as seperate fields?
View 3 Repliesi have my .xml files written like:
vb.net
<?xml version="1.0" encoding="utf-8"?>
<hiddenFields>
[code]....
I'm trying to read the values but i'm not having much luck, i have this:
vb.net
Function functionLoadHiddenFields(ByVal fileLocation As String)
Try
[code]....
i'm not to sure how to get the individual values?
I have a program where I'm writing an xml file and later the same program is to read it. I'm writing the file just fine and get this output:
[Code]...
I'm trying to read lines from a file using:Dim FileLine As String = ""Dim File As Integer = FreeFile()
Open "C:ext.txt" for Line Input # File But I get this error: 'Open' is not declared. File I/O functionality is available in the 'Microsoft.VisualBasic' namespace.
I tried to add Microsoft.VisualBasic as a reference, but it didn't work.
here is my current code.
[code]...
Now that aint workin. What i want it to do is read and compare usernames and passwords of text box 1 and 2 with 2 text files on my website. I am not caring about encryption at this piont so plz dont reply about the security of this method i know the risks. What i need is some source code i can look at witch has a simular method to mine
I have several quesions about reading/writing structures from/to files.In a scenario when I open a data file having its own header and variable data fields I create a structure that represents a header consisting of 9 bytes:
Public Structure HeaderInfo
Public DataField1 As Integer
Public DataField2 As Byte
Public DateField3 As Integer
End Structure
I'm using this code for the time being:
vb.net
Public Function ReadHeader(ByVal FileName As String) As HeaderInfo Dim ReturnInfo As HeaderInfo Try Using br As New IO.BinaryReader(New IO.FileStream(FileName, IO.FileMode.Open, IO.FileAccess.Read, IO.FileShare.Read)) With ReturnInfo
[code]....
The first question is - can I fill the structure directly somehow? Some structures are very long and filling them this way will be tedious. For example, if I know the length of the structure I could read the needed number of bytes in a byte array and somehow marshal these bytes into the structure.I can use Marshal.PtrToStructure, but then I would need to get an IntPtr of my byte array. I use <Serializable()> attribute for my structure.
Here's what I have that Doesn't work (I have one button, one OpenFileDialog, and a label named Status):
Public Sub ProcessBytes(ByVal Bytes() As Byte)
Status.Text = "Status: Processing . . ."
Try
[code].....
I've got a program which reads a text file, in this file there are 2 or 3 lines between paragraphs. However when displaying in my textbox on my form i have 14-18 lines. Why? and how can I remove them?
View 3 RepliesOk so there is an XML file for a program that already exists that stores a list of files along with other information.I need to open this file and read the file names and then potentially add files to it if they DO NOT already exist in the file.It is very important that I not wipe the XML file and have to write it from scratch every time.
View 4 RepliesI made this
vb TextBox1.Text = GetWebSiteSource("my url")
Dim lines As New List(Of String)(IO.File.ReadAllLines(TextBox1.Text))
Tsteamid1.Text = lines(1)
IO.File.WriteAllLines(TextBox1.Text, lines.ToArray)
vb
[Code]...
I have some files that contain strings and an image.I have an offset 0x068 (&H68) this is constant between all the files theoffset contains the offset of the info in the file example would be 0xE9400question being how to seek to 0x068 then seek to the new offset of say 0xE9400?then starting from 0xE9400 get Int from offset 0 size 2 bytesimage from offset 32 size 512 bytesThe icon is a 32x32 picture formed out of 4x4 16 color tiles and a single 16 color palette. Pallet offset is 544 size 32string offset 832 size 128 chars 256 bytes (unicode)I can read the first part of the header and return the string there
Dim header1(11) As Byte
Dim fileOpen As IO.FileStream = IO.File.Open(TextBox1.Text, IO.FileMode.Open, FileAccess.Read)
[code]....