Converting a binary string representation into binary array in C#

Yan Cui

I help clients go faster for less using serverless technologies.

Stumbled across this question on StackOverflow the other day, definitely one for the interview! The question goes:

How do you convert a string such as “01110100011001010111001101110100” to a byte array then used File.WriteAllBytes such that the exact binary string is the binary of the file. In this case it would be the the text “test”.

Here’s my take on the answer :-)

var binaryStr = "01110100011001010111001101110100";

var byteArray = Enumerable.Range(0, int.MaxValue/8)
                          .Select(i => i*8)    // get the starting index of which char segment
                          .TakeWhile(i => i < binaryStr.Length)
                          .Select(i => binaryStr.Substring(i, 8)) // get the binary string segments
                          .Select(s => Convert.ToByte(s, 2)) // convert to byte
                          .ToArray();
File.WriteAllBytes("C:\temp\test.txt", byteArray);

Whenever you’re ready, here are 3 ways I can help you:

  1. Production-Ready Serverless: Join 20+ AWS Heroes & Community Builders and 1000+ other students in levelling up your serverless game. This is your one-stop shop for quickly levelling up your serverless skills.
  2. I help clients launch product ideas, improve their development processes and upskill their teams. If you’d like to work together, then let’s get in touch.
  3. Join my community on Discord, ask questions, and join the discussion on all things AWS and Serverless.

Leave a Comment

Your email address will not be published. Required fields are marked *