Binary file output for fixed length string - vb.net

I am trying to write a binary file which also has a string which i want to have as fixed length in vb.net. I tried lset, padleft in debug, the value returned is correct but in the output file, the first character before the string is the fixed length i specified. why does the binary writer write the additional char ?

I found out that if if you don't want or need the length byte you can call Write with a Char [] array instead of a String

Related

Labview converting hexformatted string to ascii

In labview I am trying to convert a hex string to ascii format. For example if I have a hexstring like: 09124E4F21CD0024FFFFFFFFFFFFFFFF the ascii version of this is : NO!Í or basically a bunch of illegible symbols. I tried using the labview functions of converting hexstring to number but they didn't work. How would I convert the ascii part to hexformatted ascii?
Hexadecimal String to Number works fine, but only for a hex string that represents a number that can be stored as a numeric data type:
If the input string represents a number outside the range of the
representation of number, number is set to the maximum value for that
data type.
Your example input is 128 bits long whereas the longest integer data type in current LabVIEW is 64 bits.
You can use this function, but you need to convert the input one byte at a time:
Create a While Loop and add a shift register. Initialise the shift register with your input string.
Inside the loop, wire the string from the shift register to the string input of a Search/Split String function
Wire a numeric constant of 2 to the offset input - i.e. split the string into the first two characters, and the rest
Wire the match + rest of string output to the right-hand shift register terminal
Wire the substring before match output to a Hexadecimal String to Number function
Wire the default input of this function to a numeric constant with value 0 and type U8
Wire the output of this function to the right-hand side of the While loop and make the terminal indexing (via right-click)
Use an Empty String/Path? function to exit the While loop when the string being passed back into the shift register is empty.
The output from the indexing terminal you created will now be a U8 (byte) array containing the data converted from the input string. If you want it in string form you can convert it using Byte Array to String.
This assumes that your input string is always a multiple of 2 characters in length. If you need it to handle an input such as "3F2" you'll need to check for this and do something to the input (I'll let you figure out what) before passing it into your loop.

Bro convert hex string to int

I am using bro to read bytes directly of the payload of a packet.
I have a string value "\x10" and I want to get the decimal value of off that.
I know that bro support directly printing hex to decimal:
print 0x10;
Question is, how do I convert that string similarly to its integer version?
The best you can do is strip off the "\x" portion, and run it through 2 BIFs:
bytestring_to_count(hexstr_to_bytestring("10"));

Convert 4 Byte String Array of Hex to Decimal

I am trying to convert a string of 4 bytes in a string to an integer number in LabView, currently I am using the string subset to break apart my string and then storing it into a String Indicator on the front panel, however, I need to convert that string to an int so I can show the decimal value as well as convert it from inches to mm. Here is what I'm doing now:
I've tried converting to double using the convert string to double functions as well as I've tried splitting it up using the index array...can't quite seem to get an int out ever. Thanks!
Do as Ton Plomp said and use the Scan From String block. However, in yours, you don't want to separate with commas and with spaces. Just do:
%x%x%x%x
And that should do it for ya. Don't forget to pull the scan down so you have 4 outputs.
You can use Scan from string with the following format string:
%x
You can expand the scan from string to scan multiple items at once.

Convert a file to Binary or Hexadecimal

So I have a file that I need to have in either binary or hex format. Everything that I've been able to find basically says to store the text in a string and convert it to binary or hex from there, but I cant do it this way. The file was written using its own private character set that uses null and system hex codes, so notepad doesn't know what to do with these characters and replaces it with wrong characters and spaces. This distorts the information so it wont be correct if I try to convert it to binary/hex.
I really just need to have the binary/hex information stored in a string or text box so I can work with it. I don't really need it to be saved as a file.
Never mind, I finally figured it out. I used a file stream to read the data byte by byte. I didn't understand how to convert this as the first byte data in the array was showing as 80 when i knew the binary data should've been "1010000" (i didn't realize at that time that 80 was the decimal format).
Anyways I used the bitconverter.tostring and it put everything together and converted it to hexadecimal format. So i'm all good now.

VBA - Read file byte by byte on system with Asian locale

I am trying to convert a file from binary to text, by simply replacing each character with the hexadecimal code. For example, character 'c' will be replaced by '63'.
I have a code which is working fine in normal systems, but it breaks down in the PC where I need to use it as it has default locale set to Chinese.
I am using the following statements to read a byte -
ch$ = " "
Get #f%, , ch$
I suspect there is a problem when I am reading the file byte by byte, as it is skipping certain bytes because they form composite characters. It's probably reading 2 bytes which form an Asian character as one byte. It is thus forming a much smaller file than the expected size.
How can I read the file byte by byte?
Full code is pasted here: http://pastebin.com/kjpSnqzV
Your suspicion is correct. VB file reading automatically converts strings into Unicode from the default code page on the PC. On an Asian code page, some characters are represented as more than one byte.
I advise you to use a Byte variable rather than a string - that will stop VB being over helpful.
Dim ch As Byte
Get #f%, , ch
Another possible problem with the original code is that some byte sequences are illegal on Asian code pages (they don't represent valid characters). So your code could experience errors for some input files, but presumably you want it to work with any file.