private void btnRecord_MouseUp(object sender, MouseEventArgs e)
        {
            DateTime now = DateTime.Now;

            string fileTempDir = SdkUtils.GetRevFileTempDir();
            string filename    = String.Format("{0}_{1}", FileNamePrefix, now.ToString("MMddHHmmss"));
            string wavFile     = filename + ".wav";
            string amrFile     = filename + ".amr";
            string wavFilePath = Path.Combine(fileTempDir, wavFile);

            // 保存为wav格式
            recorder.EndRecordSound(wavFilePath);

            if (File.Exists(wavFilePath))
            {
                AudioConverter.ConvertToAmr(fileTempDir, wavFile, amrFile);
                AudioFileName = Path.Combine(fileTempDir, amrFile);
                this.Close();
            }
            else
            {
                //错误
            }
        }