Snippet to create a hash as a hex string

CreateHash.cs

        public static async Task<string> CreateHash(Stream stream)
        {
            byte[] b;
            using (var ctx = new System.Security.Cryptography.SHA256Managed())
            {
                var input = await stream.ReadDataAsync();
                b = ctx.ComputeHash(input);
            }

            return string.Join(string.Empty, b.Select(i => i.ToString("X2")));
        }