Converting binary to ascii text

[MCubitt]

In order to use teh instr function over a large binary file, I convert it to text using:

' Convert Binary to ASCII
Function BinaryToString(Binary)
  dim S
  For I = 1 To LenB(Binary)
    S = S & Chr(AscB(MidB(Binary, I, 1)))
  Next
  BinaryToString = S
end function

It's incredibly slow, even for 1Mb files which I don't consider large.

Is there a faster way please?!

thanks


Applications Support
UK

 

[trollacious]

Have you tried the built-in function

CStr(expression)

?

Lee

 

[MCubitt]

Yep, just did.. did not convert binary stream.

thanks


Applications Support
UK

 

[MCubitt]

Hi again,

It seems cstr does not work at all for bin to string, I tried it at stream and single byte level

sorry!



Applications Support
UK

 

[tsuji]

Hello MCubitt,

From the look of your script, I would think you might have read this good article, so I don't know...

http://www.motobit.com/tips/detpg_binarytostring/

regards - tsuji

 

[MCubitt]

Tsuji,

thanks, that's where I took the original from.

Using the enhanced version did not work... or at least, did not appear to. Perhaps I shoudkl try again!

Thanks


Applications Support
UK

 

[MCubitt]

oh, step 2 DID work and very quickly.

Thanks for assisting me to re-look!

thanks


Applications Support
UK

 

[tsuji]

MCubitt, that's reassuring. Thanks. - tsuji

 

[Sheco]

Well that improved version still uses string concatination so if the file gets big enough then your performance problem will return.

An alternate approach would be to use an array. This method still converts the characters one at a time but it puts each one into an element of an array. Once all of the characters are converted, the Join() function is used on the array.

Function MagicArray(Binary)
    Dim L
    Dim BigArray()
    Dim Counter
    
    L = LenB(Binary)
    ReDim BigArray(L)
    
    For Counter = 1 To L
        BigArray(Counter - 1) = Chr(AscB(MidB(Binary, Counter, 1)))
    Next
    
    MagicArray = Join(BigArray, "")
End Function