Strange Notepad++ HEX-editor plugin

Question

The goal is to write byte array to file. I have byte array fits[] with some bytes and then:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace _32_to_16
{
    class Program
    {
        static void Main(string[] args)
        {
            byte[] fits = File.ReadAllBytes("1.myf");
            byte[] img = new byte[fits.Length / 2];
            for (int i = 0; i < fits.Length; i += 4) //Drops 2 high bytes
            {
                img[i/2] = fits[i + 2];
                img[i/2 + 1] = fits[i + 3];
            }
            File.WriteAllBytes("new.myf", img);
        }
    }
}

Before writing to the file img[] has same values:

img[0]=0x31
img[1]=0x27
img[2]=0x31
img[3]=0xe2
and so on...

After writing to file, in HEX editor i see

00000000: 31 27 31 3f and other wrong values.

Sometimes, with other fits[] values, img[] array write correctly to file. What I`m doing wrong?
File for test 1.myf (which makes wrong results) https://www.dropbox.com/s/6xyf761oqm8j7y1/1.myf?dl=0 File for test 2.myf (correct writes to file) https://www.dropbox.com/s/zrglpx7kmpydurz/2.myf?dl=0

I simplified the code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace _32_to_16
{
    class Program
    {
        static void Main(string[] args)
        {
            byte[] img_correct = new byte[8] { 0xbd, 0x19, 0xbd, 0x72, 0xbd, 0x93, 0xbd, 0xf7 };
            File.WriteAllBytes("img_correct.myf", img_correct);

            byte[] img_strange = new byte[8] { 0x33, 0x08, 0x33, 0xac, 0x33, 0xe3, 0x33, 0x94 };
            File.WriteAllBytes("img_strange.myf", img_strange);
        }
    }
}

in HEX-editor img_correct.myf looks like this: bd 19 bd 72 bd 93 bd f7

in HEX-editor img_strange.myf looks like this: 33 08 33 3f 3f 3f

user_7072995 · Answer

For Full Width Colon "：" the correct Unicode format is : U+EF1A

But in NotePad ++ the "：" in Hex Editor show "EFBC9A" and not "EF1A".

Because this is an UTF8 Encoding & this is not in the Unicode format.

If I put "EFBC9A" in another editor, it show the Korean character "벚".

When you direct type in Hex Editor, make sure to use UTF8 encoding, but when you are not in Hex Editor, make sue to use Unicode Format and not UTF8 encoding.

So people is confusing with UTF8 Encoding and Unicode format.

By the way: the U+EF1A --> "：" can be put in folder name in Windows System.

Strange Notepad++ HEX-editor plugin

3 Answers