System.Data.IDataReader extension method to fully read the bytes from a large binary column

DataReaderExtensions.cs

using System.Data;
using System.IO;

namespace Extensions.Data {

    public static class DataReaderExtensions {

        /*
         * Extension method on IDataReader that reads the entire contents of a large binary column using a single method call.
         * Sample usage:
         *   byte[] bytes = reader.GetBytes(columnIndex);
         */
        public static byte[] GetBytes(this IDataReader reader, int column) {
            using (MemoryStream ms = new MemoryStream()) {
                byte[] buff = new byte[8192];
                long offset = 0L;
                long n = 0L;
                do {
                    n = reader.GetBytes(column, offset, buff, 0, buff.Length);
                    ms.Write(buff, 0, (int)n);
                    offset += n;
                } while (n >= buff.Length);
                return ms.ToArray();
            }
        }
    }
}

n = reader.GetBytes(5, offset, buff, 0, buff.Length);

You hard-coded the column index, should be column instead of 5.

Yes, I found that as well when I constructed a unit test, post-hoc. Thanks for the comment.