[c#] How to read file binary in C#?

I want to make a method that takes any file and reads it as an array of 0s and 1s, i.e. its binary code. I want to save that binary code as a text file. Can you help me? Thanks.

This question is related to c# binary

The answer is


Quick and dirty version:

byte[] fileBytes = File.ReadAllBytes(inputFilename);
StringBuilder sb = new StringBuilder();

foreach(byte b in fileBytes)
{
    sb.Append(Convert.ToString(b, 2).PadLeft(8, '0'));  
}

File.WriteAllText(outputFilename, sb.ToString());

Well, reading it isn't hard, just use FileStream to read a byte[]. Converting it to text isn't really generally possible or meaningful unless you convert the 1's and 0's to hex. That's easy to do with the BitConverter.ToString(byte[]) overload. You'd generally want to dump 16 or 32 bytes in each line. You could use Encoding.ASCII.GetString() to try to convert the bytes to characters. A sample program that does this:

using System;
using System.IO;
using System.Text;

class Program {
    static void Main(string[] args) {
        // Read the file into <bits>
        var fs = new FileStream(@"c:\temp\test.bin", FileMode.Open);
        var len = (int)fs.Length;
        var bits = new byte[len];
        fs.Read(bits, 0, len);
        // Dump 16 bytes per line
        for (int ix = 0; ix < len; ix += 16) {
            var cnt = Math.Min(16, len - ix);
            var line = new byte[cnt];
            Array.Copy(bits, ix, line, 0, cnt);
            // Write address + hex + ascii
            Console.Write("{0:X6}  ", ix);
            Console.Write(BitConverter.ToString(line));
            Console.Write("  ");
            // Convert non-ascii characters to .
            for (int jx = 0; jx < cnt; ++jx)
                if (line[jx] < 0x20 || line[jx] > 0x7f) line[jx] = (byte)'.';
            Console.WriteLine(Encoding.ASCII.GetString(line));
        }
        Console.ReadLine();
    }
}

Generally, I don't really see a possible way to do this. I've exhausted all of the options that the earlier comments gave you, and they don't seem to work. You could try this:

        `private void button1_Click(object sender, EventArgs e)
    {
        Stream myStream = null;
        OpenFileDialog openFileDialog1 = new OpenFileDialog();
        openFileDialog1.InitialDirectory = "This PC\\Documents";
        openFileDialog1.Filter = "All Files (*.*)|*.*";
        openFileDialog1.FilterIndex = 1;
        openFileDialog1.RestoreDirectory = true;
        openFileDialog1.Title = "Open a file with code";

        if (openFileDialog1.ShowDialog() == DialogResult.OK)
        {
            string exeCode = string.Empty;
            using (BinaryReader br = new BinaryReader(File.OpenRead(openFileDialog1.FileName))) //Sets a new integer to the BinaryReader
            {
                br.BaseStream.Seek(0x4D, SeekOrigin.Begin); //The seek is starting from 0x4D
                exeCode = Encoding.UTF8.GetString(br.ReadBytes(1000000000)); //Reads as many bytes as it can from the beginning of the .exe file
            }
            using (BinaryReader br = new BinaryReader(File.OpenRead(openFileDialog1.FileName)))
                br.Close(); //Closes the BinaryReader. Without it, opening the file with any other command will result the error "This file is being used by another process".

            richTextBox1.Text = exeCode;
        }
    }`
  • That's the code for the "Open..." button, but here's the code for the "Save..." button:

    ` private void button2_Click(object sender, EventArgs e) { SaveFileDialog save = new SaveFileDialog();

        save.Filter = "All Files (*.*)|*.*";
        save.Title = "Save Your Changes";
        save.InitialDirectory = "This PC\\Documents";
        save.FilterIndex = 1;
    
        if (save.ShowDialog() == DialogResult.OK)
        {
    
            using (BinaryWriter bw = new BinaryWriter(File.OpenWrite(save.FileName))) //Sets a new integer to the BinaryReader
            {
                bw.BaseStream.Seek(0x4D, SeekOrigin.Begin); //The seek is starting from 0x4D
                bw.Write(richTextBox1.Text);
            }
        }
    }`
    
    • That's the save button. This works fine, but only shows the '!This cannot be run in DOS-Mode!' - Otherwise, if you can fix this, I don't know what to do.

    • My Site


You can use BinaryReader to read each of the bytes, then use BitConverter.ToString(byte[]) to find out how each is represented in binary.

You can then use this representation and write it to a file.


Use simple FileStream.Read then print it with Convert.ToString(b, 2)


using (FileStream fs = File.OpenRead(binarySourceFile.Path))
    using (BinaryReader reader = new BinaryReader(fs))
    {              
        // Read in all pairs.
        while (reader.BaseStream.Position != reader.BaseStream.Length)
        {
            Item item = new Item();
            item.UniqueId = reader.ReadString();
            item.StringUnique = reader.ReadString();
            result.Add(item);
        }
    }
    return result;