I am writing a windows desktop application in visual basic and I need it to connect to a SQL database, take a rows unique id, and using that number generate a file from the binary data that is stored in the SQL database and save it to a file directory. The part that is hanging me up is the creating the file from the binary SQL data.
View 2 RepliesI am using VB2005 and trying to put an application together.What it needs to do is retrieve information from a binary file, possibly alter that information, and put it back into a new file.The file is a .wav file with data appened to the end. There is an additional section at the end of the .wav file which stores xml data.I have found that if I open this in a hex editor and make a 1:1 swap on any of the bytes that the application that the file is for can still read the XML.If I tried to add or remove characters from the XML then it would not read. I located a header byte and incremented it to resolve this.
This worked as an excellent bandage to do conversions where the data always needed to be changed to the same thing.What I have been asked to do is build logic that allows for different things to happen depending upon what data is contained within the file.The method that I am currently trying to impliment is:
Read through the file with a system.io.binaryreader
Searche for a bytestream that will signal data is coming
For example:
If System.IO.File.Exists("C: est estread.wav") Then
Dim findit() As Integer = New Integer() {&H3C, &H55, &H73, &H72, &H44, &H65, &H66, &H30, &H31, &H30}
Dim i As Integer[code].....
And then extract all the data till the end of element marker "<" It seemed like there should be a better way and I was looking for some insight. If I proceed with this method, I will have to read the file one time to gather the information and then a second time to write it all out with the header modified for length.This is my first experiene with working with binary files in this way.Also,I've been experiementing with building a string and slapping it back in at the end using the binarywriter.write(string) method.I noticed that it was putting in header characters before the string.These seem to change if I change the length of the string.At one point it was d0 07. Later it became e7 07. Does anyone know of a way to prevent this header from being inserted?
I tried a for each loop to grab all of the characters from the string, convert them to a byte array and deposit the byte array into the file, but the header remained the same. When I write the byte array generated from a system.io.binaryreader I do not get this header.
i have a requirement where in i have to update the information of a record with new values.how to open the binary file and update with the new information.The existing binary file contains 5 records with serial nos.now i want to update the information of sno 1.i am using filestream, binary reader ,binarywriter SureshThere is an Island of Opportunity In the Middle of Every Difficulty
View 1 Repliesi have to update an existing binary file with new information.
binary file contains records from 1 to 5 each record contains different values one integer and five strings.
no i have to update the 1 record with the new information .how do i do that.
i am using filestream,binary reader and binary writer.
Pwd_FS = New FileStream("test.bin", FileMode.Open, FileAccess.Read)
after reading the contents of the record i will assign new values to the recorod writing back should i use
Pwd_FS = New FileStream("test.bin", FileMode.Append, FileAccess.Write) if i use append i am not able to seek to the starting point.
i'm beginer in this forum and new in vb6.how to generate random number in vb6?
is it posible to represent variable in binary?
How may one get information that was used to programatically generate asp controls?For example, I pulled a DataTable of user objects from the database and have organized them on a page, listing groupings such as a list of employees directly under the employer for each employer. On the page, I list each user's Username as a LinkButton. When I click one of these employees, I want to redirect the page (which is easy) and set a session variable to the selected user's UserId (which seems not so easy). How can I pull this UserId value back? These elements are not hard-coded with nice names (as they are generated in a for each loop).
Code from comment below:
Dim lnkbtnPm As New LinkButton ' is my link button. '
lnkbtnPm.Text = pmDr.Item("Username") ' where pmDr is my datarow. '
lnkbtnPm.CommandArgument = pmDr.Item("UserId")
[code]....
i need to read binary file and in this file found the string and replace it with other one and save the file afterwords. I found many example to read binary, but to find and replace is for me mistery.
View 3 RepliesI 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?
I've gone through about 16 hours and two packs of cigarettes trying to figure this out. First a little background. I was using 6.0 up until 2004 when I went to prison. I'm out now, and trying to relearn the trade, using VS 2005. I'm currently porting some 6.0 code from another project, SpyCast Webcam Studio, into VB 8.0. It's disheartening, to say the least. None of the old built-in subs/functions work anymore, so I have to scour the forums to relearn each and every function.The section I'm doing now takes a snapshot from the webcam (Video API --> PictureBox --> Save as Jpeg), then upens the file to upload it to the server via HTTP POST. I've been using this code in SpyCast for years with no trouble, but I spent many hours trying to piece together the right code to open the binary file to read its contents. I pieced together two methods I found around the forums, one using FileStream() though the code I found wasn't for binary files, even though it said it was, so that code doesn't really work. Method two uses Microsoft.VisualBasic.FileOpen() and works better.
Here's the kicker. By the time I run through the rest of the rigamarole of uploading the file, by the time I read it on the webserver, it's *slightly* corrupted. It's a valid Jpeg, no errors, but the picture looks like when I use to watch the Playboy Channel when I was a kid scrambled with weird colors and whatnot. [code] Each "chunk" is basically one "line" of the file. It looks like a single LineInput() return is the text between two carriage returns. Am I correct? I tested this with a flat text file, and it looks true. However, That one input line returns the text or data with the carriage returns *stripped*! ***?!? =( Fine, I have no problem adding my own vbCrLf to each LineInput(), if I were opening text. but this's binary. A character could be Chr(10) or Chr(13), both of which are removed from the original file contents.So I could very well need to use something other than LineInput(), but I haven't found any other examples on the web using this method.
how I could check if a certain file is in text or binary format?I'm using VB.Net 2008 Express.
View 2 RepliesProgram to convert binary pdf file to tiff file in VB.NET..?? We can use third party tools also..???
View 1 Replieshowever, I am stuck at BinaryReader.actually this is what i am trying to acheive through VB.NET.say for the following file type :
JPG file = FF D8 FF E0
BMP file = 42 4D BE 4E
PNG file = 89 50 4E 47
GIF file = 47 49 46 38
the above are the 4-byte headers in Hex(raw) I need to read these headers of any given file using OpenFileDialog using Button1_click event,on selection of any given file(*.* filters ON)it should use the BinaryReader and look for only 4-bytes starting from offset 0, and it should not go to EOF marker (-1).and have a variable to hold this 4-byte header value, to run this in a database table which will check the same header value in the table and would display the corresponding extension of the file. from the table.
I can do this using case, if then...etc.however, I have to do it using Database and also i need to check for testing purpose to use MsgBox() to display this variable which is holding the 4-byte header.however, the MsgBox doesnt allow anything other than String.
PS: I tried studying the methods like:
FileOpen/Seek/Peek/ReadBytes().
but still not sure how to get them work.
I need to save a datatable to a binary file , in binary format , in order to make the process fast because the datatable may contain up ten millions rows. So , XML is not favorable because it makes the file large sized , and the process will be slow.
I managed to save the datatable to a binary file , and it works fine , but the problem when I try to add new rows to the existing binary file (using a datatable with the same schema , but different rows data) , it copies the schema of the datatable to the binary file, making it very large.
[Code]...
I have a Binary file that has data represented in 1604 bytes. each set of data within these groups is composed of short (2 byte) numbers. I would like to creat a vb.net program that takes this binary file then converts it to numbers, and then places it within a new text file. How would I accomplish this?
View 9 RepliesI am reading a Binary file using BinaryReader in VB.NET.The structure of each row in the file is:
"Category" = 1 byte
"Code" = 1 byte
"Text" = 60 Bytes
Dim Category As Byte
Dim Code As Byte
[Code]...
i have a file any type of file and i want to display the binary of that file the (01) of that file can do it also i want to display the hexa which it better and faster if u just can put me on track
View 4 Repliesis anyone know how to get BMP image from binary file?
Offset Length Description
100 4 BMP_offset
268 4 Cover_size
296 4 Cover_offset
I've been using VB.NET for a few years now, but I never really got into binary files. How do you add onto binary files from the beginning? Here is some example code:
Dim writer As New IO.BinaryWriter(IO.File.Open("C:\Users\Dameon\Desktop\newbin.bin", IO.FileMode.CreateNew))
writer.Write("HELLO WORLD!")
[Code]....
How can I add onto the beginning of the file without overwriting what's already there? I'm trying to make my own file archive format. I have the compressing/decompressing down, but now I'm implementing adding/deleting a file after the archive already made.
I have existent binary files with this structure[code]...
View 13 RepliesI need make an application that gets binary code from a file, such as a .exe, (in 8-bit form) and display the charectors in a RichTextBox .BUT! The catch is I need it to do the process REALLY fast, like in a 5th 0.5 of a second. I have a method but it takes way to like, sometimes 5 seconds for 1 file, which isn't what I want This is the code I have:[CODE]......
View 9 RepliesI am not exactly sure how to say this, but what I want to do is to write a series of strings converted to their hex notation to a binary file. Here is what I have[code]....
View 8 RepliesHow do I change bytes [text stored in those bytes] in a binary file?
I have a little function that read bytes 335-343 [For Keyer] and bytes 344-352 [for verifier] and displays it. These bytes store who the keyerID and VerifierID of a data entry file are. From time to time the Verifier Resumes the file [to insert new records], and his/her name gets stored in the KeyerID bytes. So if the original keyer had lots of errors, the new verifier now becomes the owner of this file and the errors are attributed to him/her [not fair]. He/She gets penalized when there are lots of errors.
My question to you is, how do I change the content of those bytes and save it to the file, without damaging any part of the file? I want to save 'H345' in those bytes, [H345 is an example of a Keyer/Verifier ID]
note - as of now I am using 010 Editor [binary editor]to manually change those bytes. When I use this editor, I can see the text portions for those bytes.[code]...
Iam working in a project need converting a wave file to binary..converting a file of such format(wave) to binary text in asp.net? I need that cause i want to cut the original file to many files, and add additional parts of the same type to them and combine them together in a one file again..
View 2 RepliesRecently I experiment with the binary file type. I have this structure[code]...
It works. And now, in the load event of the form I want to know, how many records (structures) are stored in the file.
Another question: how can I search and seek in the file (structure to structure, not byte to byte)?
I'm trying to save a binary file stored in a SQL database with a SaveDialog, the function RetrieveFile retrieves the specified file from the database as a Byte array, here's what I have so far:
Private Shared Function RetrieveFile(ByVal filename As String) As Byte()
Dim connection As New SqlConnection("Data Source=SERVERSQL2008;Initial Catalog=NorthPole;Integrated Security=True")
Dim command As New SqlCommand("SELECT pcfFile FROM Items WHERE pcfFileName=@Filename", connection)
command.Parameters.AddWithValue("@Filename", filename)
connection.Open()
[Code] .....
Files are saved as "SqlDbType.VarBinary" within the database.
I get: "Index was outside the bounds of the array." on:
Dim retrievedBytes As Long = reader.GetBytes(1, startIndex, buffer, 0, ChunkSize)
The MemoryStream appears to not be retrieving the data yet the SQL syntax is correct.
Join Date: Dec 10
Posts: 10
caba11 is an unknown quantity at this point (<10)
How to save binary file to database. Ineed to save files into database. I cant find why it is not working...
This is my code:
Public Sub importfiles(ByVal sFileName As String)
Dim cnSQL As SqlConnection
Dim cmSQL As SqlCommand
Dim strSQL
'Validate form values
[Code] .....
Without try it says "cmSQL.ExecuteNonQuery()"-"Failed to convert parameter value from a DataGridViewTextBoxColumn to a Int32."
I have a VB.NET dll which pulls out binary data from and opens it as a pdf. It works fine if I create a file on the user's machine and then open that. What I want to do, however, is just open it in Adobe without creating the file on their machine first (there's customer data in the file and we don't want copies of it sitting around unecessarily).
It's possible in ASP.NET to just stream the data to a browser and open it in that without creating the file, but I can't find a similar methodology for doing that straight to Adobe. Does anyone know if this is even possible or do I have to create the file in order to have it open?
can someone teach me how to open the file with binary mode in VB.NET?
View 6 Repliesreading a 16bit binary file (tiff image). Since the file is in 16bit, pixels of the file stores values ranging from 1200 to 4500. I want to retrieve those values. I used ReadUInt16 since the file has a 2byte data type but keep getting EnfofStreamException Unhandled error.
Dim f1 As New System.IO.FileInfo(TextBox2.Text)
fLen1 = f1.Length
Dim snglRead As Single
Dim i As Integer
[code]....
To read a record in a binary file in VB^ I would define a type with all the fields specifying strings as STRING * whatever the length of the field was.
For example:
Type Record
Field1 as string *15
Field2 to as string * 20
Field3 as String * 10
field4 as byte(10)
End Type
Dim filerecord as record
I would the open my binary fiel and do a Get#1,, filerecord
The record would be read and all the fielsd would be in place.
Now with the new Structure we cant dimension an array in the Structure And wjhen declaring strings we can't specify the length.
I tried to create structire and use a stream binary reader. and just read afixed number of bytes into the type, The program says it canvert bytes to my fiels.
So how do I do this. Or has Microsoft in their infinite wisdom left no way to do this.