public void UploadOrCombineAudioFile()
{HttpFileCollection files = HttpContext.Current.Request.Files;if (files == null || files.Count < 1)return;string upfileType = HttpContext.Current.Request.Form["upfileType"];//文件格式类型/*...省略符...*/int maxSize = 1024 * 1024 * 100;//单文件上传最大限制List<string> dirDic = new List<string> { ".mp3", ".mp4", ".pcm", ".wav" };//文件格式限制string uploadPath =  HttpContext.Current.Server.MapPath("~/AudioFile/TempFile/");//临时路径if (!Directory.Exists(uploadPath))Directory.CreateDirectory(uploadPath);string fileType = string.Empty;for (var i = 0; i < files.Count; i++){var postedfile = files[i];var inputStream = postedfile.InputStream;if (inputStream.Length > 0){string thisfileName = files[i].FileName;fileType = Path.GetExtension(thisfileName);if (postedfile.InputStream == null || postedfile.InputStream.Length >  maxSize || !dirDic.Contains(fileType.ToLower()))return;/*...我是省略符...*/int ReadLen = 0;string uploadFileName = uploadPath + thisfileName;byte[] bytes = new byte[10240];using (FileStream stream = new FileStream(uploadFileName,  FileMode.OpenOrCreate))//保存文件到指定待合并文件路径下
            {while ((ReadLen = inputStream.Read(bytes, 0, bytes.Length)) > 0){stream.Write(bytes, 0, ReadLen);}}}}List<string> filepaths = new List<string>(Directory.GetFiles(uploadPath));//获取待合并文件路径//文件合并后路径string savePath =  HttpContext.Current.Server.MapPath("~/AudioFile/ComBineFile/" +  DateTime.Now.ToString("yyyyMMdd") + "/");if (!Directory.Exists(savePath))Directory.CreateDirectory(savePath);/*...我是省略符...*/byte[] buffer = new byte[10240];string savefullName = savePath + DateTime.Now.ToString("yyyyMMddHHmmssff") +  upfileType;if (upfileType.ToLower().Equals(".mp3"))CombineMp3(filepaths, savefullName);//mp3合并else if ((upfileType.ToLower().Equals(".wav")))CombineWav(filepaths, savefullName);//wav合并/*...我是省略符...*/return;
}

//命名空间
using System.IO;
using NAudio;
using NAudio.Wave;/// <summary>
/// Mp3格式合并
/// </summary>
/// <param name="inputFiles">待合并文件路径</param>
/// <param name="outputfullName">输出文件名</param>
private void CombineMp3(List<string> inputFiles, string outputfullName)
{using (FileStream outputStream = new FileStream(outputfullName,  FileMode.OpenOrCreate)){foreach (string file in inputFiles){Mp3FileReader reader = new Mp3FileReader(file);if ((outputStream.Position == 0) && (reader.Id3v2Tag != null)){outputStream.Write(reader.Id3v2Tag.RawData, 0,  reader.Id3v2Tag.RawData.Length);}Mp3Frame frame;while ((frame = reader.ReadNextFrame()) != null){outputStream.Write(frame.RawData, 0, frame.RawData.Length);}}}
}

/// <summary>
/// wav格式合并
/// </summary>
/// <param name="inputFiles">待合并文件</param>
/// <param name="outputfullName">输出文件名</param>
private void CombineWav(List<string> inputFiles, string outputfullName)
{WaveStream waveStream = WaveFormatConversionStream.CreatePcmStream(new  WaveFileReader(inputFiles[0]));using (WaveFileWriter waveFileWriter = new WaveFileWriter(outputfullName,  waveStream.WaveFormat)){foreach (string file in inputFiles){waveStream = WaveFormatConversionStream.CreatePcmStream(new  WaveFileReader(file));byte[] bytes = new byte[waveStream.Length];waveStream.Position = 0;waveStream.Read(bytes, 0, (int)waveStream.Length);waveFileWriter.Write(bytes, 0, bytes.Length);}}
}

未完待续....