/// <summary>
        /// Sets the speed of the voicer.
        /// </summary>
        /// <param name="speedOfVoicer">
        /// Pass 0 for ExtraSlow, 1 for Slow, 2 for Normal, 3 for Fast, 4 for ExtraFast speed.
        /// </param>
        /// <returns></returns>
        public void SetSpeed(SpeedOfVoicer speedOfVoicer)
        {
            this.speedOfVoicer = speedOfVoicer;

            switch (speedOfVoicer)
            {
            case SpeedOfVoicer.ExtraSlow:
                voicerSpeed = (new PromptStyle(PromptRate.ExtraSlow));
                break;

            case SpeedOfVoicer.Slow:
                voicerSpeed = (new PromptStyle(PromptRate.Slow));
                break;

            case SpeedOfVoicer.Normal:
                voicerSpeed = (new PromptStyle(PromptRate.Medium));
                break;

            case SpeedOfVoicer.Fast:
                voicerSpeed = (new PromptStyle(PromptRate.Fast));
                break;

            case SpeedOfVoicer.ExtraFast:
                voicerSpeed = (new PromptStyle(PromptRate.ExtraFast));
                break;

            default:
                throw new InvalidEnumArgumentException("Invalid SpeedOfVoicer enum argument passed.");
            }
        }
        /// <summary>
        /// The class constructor.
        /// </summary>
        /// <remarks>
        /// By default it sets the speed of the voicer to Normal
        /// and the maximum volume of the voicer to Max.
        /// </remarks>
        public TextVoicerSpeechSynthesizer()
        {
            textVoicer     = new SpeechSynthesizer();
            messageBuilder = new PromptBuilder();

            speedOfVoicer  = SpeedOfVoicer.Normal;
            volumeOfVoicer = VolumeOfVoicer.Max;

            SetSpeed(speedOfVoicer);
            SetVolume(volumeOfVoicer);
        }