Question

we have a text file containing binary values.
say, we have a file “file.txt”,it contains binary datat, say 11001010
the size of this file is 8 bytes.
but we want these 8 bytes to be read as bits i.e. 8 bits and thus make 8 bits into 1 byte. How can we do it?
we just know the procedure:
1. take a buffer and read individual value into buffer
2.if the buffer value reaches 8,make those 8 bits into a byte and write to a file.

thanks in advance.

Answer 1

The following code reads such a text file as you describe. If the file contains a number of binary digits that is not divisible by 8, the extraneous digits are discarded.

using (var fileToReadFrom = File.OpenRead(@"..."))
using (var fileToWriteTo = File.OpenWrite(@"..."))
{
    var s = "";
    while (true)
    {
        var byteRead = fileToReadFrom.ReadByte();
        if (byteRead == -1)
            break;
        if (byteRead != '0' && byteRead != '1')
        {
            // If you want to throw on unexpected characters...
            throw new InvalidDataException(@"The file contains a character other than 0 or 1.");
            // If you want to ignore all characters except binary digits...
            continue;
        }
        s += (char) byteRead;
        if (s.Length == 8)
        {
            fileToWriteTo.WriteByte(Convert.ToByte(s, 2));
            s = "";
        }
    }
}