How to split byte array with char in c#

Question

I have a byte array and want to split this with * char I am C++/Qt developer i can do this easy with this code in Qt

QByteArray byteArray;
QList<QByteArray> byteArrayList;

byteArray = file.readAll();
file.close();

byteArrayList = byteArray.split('*');

How can i split a byte array with char in C# ?

and what is a `QByteArray`? what API does that expose? that's not an inbuilt type, so... what happens with your code? does `byterArray.split((byte)'*');` work? — Marc Gravell, Nov 21 '17 at 15:21
@TobiasTheel then - some reference to what they currently have in C# would be really useful; are they using `byte[] byteArray = ...` ? — Marc Gravell, Nov 21 '17 at 15:27
If it is a text file - why not read the file as a string, split on char, and convert the resulting array to a list of byte arrays. — PaulF, Nov 21 '17 at 15:27
Some additional information would truly be useful. Btw: http://doc.qt.io/qt-4.8/qbytearray.html — Tobias Theel, Nov 21 '17 at 15:28
We don't know what the heck you're saying! What does the char have to do with the byte array? You might as well be asking repeatedly for "cut my sandwich with a song". Are you saying the bytes should be interpreted as ASCII characters or what? We can't read your mind, so explain what it is you actually need. — itsme86, Nov 21 '17 at 15:44

score 1 · Answer 1 · answered Nov 21 '17 at 15:43

1

byte[] bytes = File.ReadAllBytes("yourtextfile.txt");
string[] x = Encoding.UTF8.GetString(bytes).Split('*');

Change encoding if needed.

answered Nov 21 '17 at 15:43

p-a-o-l-o

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from comments: "this not text file" – Marc Gravell Nov 21 '17 at 15:44
You look expert in this field, Marc: https://stackoverflow.com/questions/11816295/splitting-a-byte-into-multiple-byte-arrays-in-c-sharp – p-a-o-l-o Nov 21 '17 at 15:49
binary network clients and binary serialization formats are two areas that I've certainly spent a lot of time in.... – Marc Gravell Nov 21 '17 at 15:54

score 1 · Answer 2 · answered Nov 21 '17 at 15:44

1

I'm not sure anything is inbuilt for that, since it isn't a common scenario; however you can search by index:

(all use of string here is purely for illustration; the actual split code doesn't use that)

static void Main()
{
    // pretend this isn't text
    byte[] bytes = Encoding.ASCII.GetBytes("askdjhkas*hdaskjdhakjshdjkahs*dkujyash");

    foreach(var chunk in Split(bytes, (byte)'*'))
    {
        // cheating with text to see if it worked
        var s = Encoding.ASCII.GetString(chunk.Array, chunk.Offset, chunk.Count);
        Console.WriteLine(s);
    }
}

static IEnumerable<ArraySegment<byte>> Split(byte[] data, byte splitBy)
{
    int start = 0, end;
    while((end = Array.IndexOf<byte>(data, splitBy, start)) > 0)
    {

        yield return new ArraySegment<byte>(data, start, end - start);
        start = end + 1;
    }
    end = data.Length;
    if ((end - start) > 0)
    {
        yield return new ArraySegment<byte>(data, start, end - start);
    }
}

Note: this would be a great scenario for "span" when that lands.

answered Nov 21 '17 at 15:44

Marc Gravell

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Can you please edit the question so it is clear what supposed to happen? (Is OP looking for equivalent of `string.Split` but for arrays?) – Alexei Levenkov Nov 21 '17 at 16:08
@AlexeiLevenkov I think so, yes – Marc Gravell Nov 21 '17 at 16:09
how to add this bytes to a list of bytes List bytesList = new List(); – ARASHz4 Nov 21 '17 at 16:48
@ARASHz4 I would strongly advise against that - that is going to force you to allocate more memory. Could you live with `List>>` ? if so: `var bytesList = Split(bytes, (byte)'*').ToList();`. As I say, "span" would be idea for this and would avoid extra allocs. If you *must* duplicate all the pieces, it can be done, sure – Marc Gravell Nov 21 '17 at 17:13
@marc-gravell how to convert List > to List – ARASHz4 Nov 21 '17 at 19:05

How to split byte array with char in c#

2 Answers2