System.Security.SecureString.Copy C# (CSharp) Method

		public SecureString Copy () 
		{
			SecureString ss = new SecureString ();
			ss.data = (byte[]) data.Clone ();
			ss.length = length;
			return ss;
		}

        /// <summary>
        /// Initializes a new instance of the <see cref="Cryptkeeper" /> class.
        /// </summary>
        /// <param name="passphrase">The encryption key or passphrase represented in a SecureString. This is the preferred method of instantiating this class because it protects the key in memory.</param>
        public Cryptkeeper(System.Security.SecureString passphrase)
        {
            string err = "Cryptkeeper passphrase must be 16 characters (128-bit encryption) or 32 characters (256-bit) in length.";

            if (passphrase == null)
            {
                throw new ApplicationException(err);
            }
            if (passphrase.Length == 0)
            {
                throw new ApplicationException(err);
            }

            if (passphrase.Length > 1 && passphrase.Length <= 16)
            {
                this.keysize   = 128; // 128 bits is 16 bytes or 16 characters in UTF8
                this.keyString = passphrase.Copy();
                return;
            }

            if (passphrase.Length > 16 && passphrase.Length <= 32)
            {
                this.keysize   = 256; // 256 bits is 32 bytes or 32 characters in UTF8
                this.keyString = passphrase.Copy();
                return;
            }

            if (passphrase.Length > 32)
            {
                throw new ApplicationException(err);
            }
        }