File.WriteAllBytes does not changes file to binary 10101011

Question

I have a some confusion about the function File.WriteAllBytes.

Actually i read from an image file using

byte[] b =  System.IO.File.ReadAllBytes(textBox1.Text);

and then i wrote back the read data to a text file to see how it looks.

System.IO.File.WriteAllBytes(@"D:\abc.txt", b);

But the contents of abc.txt are not pure binary(1010110) , but they appear as :-

ëžÕwN±k›“ùIRA=Ï¥DhÔ¨í»™Êj:³0Æî(À÷«3ÚÉid¤n•O<‰-ª@–¢)cùY³Ö˜K„TûËEÇóþ}wtÑ+²=£v*NÌ!\ äji;âíÇ8ÿ ?çŠ´ö¬€Áç#µ:+ŠVÜ„©³Û?çù~VèÖ·ÂËSŠE7RH8}GJGfT?Ý?çüÿ œÌÊR"6ÓŠY¬Š¬L§|n¹> ÷’ÃU{D®tvE!3** Ý× õ¨ã(¨qžO§ùÿ >Ó¥¤…K€@N{ñM(ÊÅ€ûÃŒRtj/²Æ¤¶¹RÁŽxqþÏó@KŒînçš˜æ0C/-Ž1Mu>oÊ }é5(Q¢i±pIôÀôÿ ?çÒÂB-á.ãï©Ú}êB®æÇÌyÿ ?çüU¥mã$”ã ‚DiFQ¸'µ,ARGLäc¯4%ËŸÃœsŸóù~H 3d‚zŠ‡Ø........................................

Are the binary 1s and 0s getting converted to some other number system comprising of so many symbols ??

If you read all bytes, don't change anything, and then write all bytes to another file, then it only makes sense to me that you get the same file. I can understand thinking that `WriteAllBytes` does something else, but I can't understand thinking that `ReadAllBytes` followed by `WriteAllBytes` creates a completely different file. — , Jan 13 '14 at 12:07
file is the same .Its just the way i am opening the file. If you try to open an image in a textpad or notepad , it would appear as above. But i am intrested in looking 1s and 0s — anurag, Jan 13 '14 at 12:14
Open the file in a hex editor and you will see the bytes. You won't see 1s and 0s but rather the hex values (0-F). — BryanJ, Jan 13 '14 at 12:15

score 1 · Answer 1 · answered Jan 13 '14 at 12:15

Each byte in the file is comprised of 8 bits. When you use ReadAllBytes, you get an array of byte instances, where each byte represents a number between 0 and 255 (inclusive). One representation of the number 86 that is readable by humans is 01010110. However, when you use WriteAllBytes, it writes the sequence of bytes in the original form. Notepad is then loading the file and displaying each byte as a single character (or in some encodings treating multiple bytes as a single character to display). However, if you were to write "01010110" to a file such that Notepad shows those numbers, you would actually end up writing 8 bytes, not 8 bits, like this, where each set of 8 bits represents the digit '0' or '1':

00110000 00110001 00110000 00110001 00110000 00110001 00110001 00110000

This makes sense if there are only 256 unique symbols in the converted file. — anurag, Jan 13 '14 at 12:18

score 1 · Accepted Answer · edited May 23 '17 at 12:08

1

A text-viewer like NotePad will try to interpret the bytes as text, probably it will interpret the bytes as Unicode.

If you want to see the actual 0's and 1's then read in the image as bytes and convert the byte array to a string of 0's and 1's, for this you could use:

public static string ByteArrayToString(byte[] ba)
{
   string hex = BitConverter.ToString(ba);
   return hex.Replace("-","");
}

The conversion function is copied from here (accepted answer). Remember, this string will not anymore be interpretable as image, essentially this will simply be a large string of 0's and 1's.

edited May 23 '17 at 12:08

Community

1
1

answered Jan 13 '14 at 12:20

Daniel

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Yes it worked . Now the text file outputs as FFD8FFE000104A4649460001010100C800C80000FFE114084578696600004D4D002A00000008000C010F00020000000348500... – anurag Jan 13 '14 at 12:30

File.WriteAllBytes does not changes file to binary 10101011

2 Answers2