C#

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

        private void SearchLink_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            if( File.Exists("C:\\Users\\Jase\\Desktop\\Test.txt"))
            {
            // File to search.
            string FileName = "C:\\Users\\Jase\\Desktop\\Test.txt";

            // Reads file to end.
            StreamReader SearchText = new StreamReader(FileName);
            string ReadAll = SearchText.ReadToEnd();

            // SearchTextBox.Text contains string to search for.
            SearchText.Close();
            string regMatch = SearchTextBox.Text;

            // If the string has been found, do something.
            if (Regex.IsMatch(ReadAll, regMatch))
            {
                MessageBox.Show("Found\n" + "" + regMatch);
            }
            else
            {
                MessageBox.Show("Not found\n");
            }
            }
            else
            {
                MessageBox.Show("Non-Existant File.");
            }
        }

String path = "path to your file";
System.IO.StreamReader reader = new System.IO.StreamReader(path);
String data = reader.ReadToEnd();
byte[] buffer = Encoding.ASCII.GetBytes(data);
System.Collections.BitArray bits = new System.Collections.BitArray(buffer);

//and then do whatever manipulation you have to do