/// <summary>
/// 下载文件
/// </summary>
/// <param name="fileNames">需要下载的文件集合</param>
/// <param name="mark">标记</param>
/// <param name="saveDirectoryPath">保存路径</param>
/// <param name="cancellationToken">异步取消命令</param>
/// <returns>下载任务（是否成功、原因、失败文件名）</returns>
public static async Task <TransferResult <List <string> > > FileDownload(List <string> fileNames, string mark, string saveDirectoryPath, System.Threading.CancellationToken cancellationToken = new System.Threading.CancellationToken())
{
var result = new TransferResult <List <string> >()
{
Message = $"文件保存路径不正确：{saveDirectoryPath}"
};
if (!System.IO.Directory.Exists(saveDirectoryPath))
{
return(await Task.Run(() => result));//文件路径不存在
}
if (fileNames.Count == 0)
{
result.Message = "未包含任何文件";
return(await Task.Run(() => result));//文件路径不存在
}
result.Message = "未能连接到服务器";
FileRequest request = new FileRequest()
{
Mark = mark
}; //请求数据
request.FileNames.AddRange(fileNames); //将需要下载的文件名赋值
var lstSuccFiles = new List <string>(); //传输成功的文件
string savePath = string.Empty; //保存路径
System.IO.FileStream fs = null;
Channel channel = null;//申明通信频道
GrpcService.FileTransfer.FileTransferClient client = null;
DateTime startTime = DateTime.Now;
try
{
(channel, client) = GetClient();
using (var call = client.FileDownload(request))
{
List <FileReply> lstContents = new List <FileReply>();//存放接收的数据
var reaponseStream = call.ResponseStream;
//reaponseStream.Current.Block数字的含义是服务器和客户端约定的
while (await reaponseStream.MoveNext(cancellationToken))//开始接收数据
{
if (cancellationToken.IsCancellationRequested)
{
break;
}
if (reaponseStream.Current.Block == -2)//说明文件已经传输完成了
{
result.Message = $"完成下载任务【{lstSuccFiles.Count}/{fileNames.Count}】，耗时：{DateTime.Now - startTime}";
result.IsSuccessful = true;
break;
}
else if (reaponseStream.Current.Block == -1) //当前文件传输错误
{
Console.WriteLine($"文件【{reaponseStream.Current.FileName}】传输失败！"); //写入日志
lstContents.Clear();
fs?.Close(); //释放文件流
if (!string.IsNullOrEmpty(savePath) && File.Exists(savePath)) //如果传输不成功，删除该文件
{
File.Delete(savePath);
}
savePath = string.Empty;
}
else if (reaponseStream.Current.Block == 0) //当前文件传输完成
{
if (lstContents.Any()) //如果还有数据，就写入文件
{
lstContents.OrderBy(c => c.Block).ToList().ForEach(c => c.Content.WriteTo(fs));
lstContents.Clear();
}
lstSuccFiles.Add(reaponseStream.Current.FileName); //传输成功的文件
fs?.Close(); //释放文件流
savePath = string.Empty;
}
else//有文件数据过来
{
if (string.IsNullOrEmpty(savePath))//如果字节流为空，则说明时新的文件数据来了
{
savePath = Path.Combine(saveDirectoryPath, reaponseStream.Current.FileName);
fs = new FileStream(savePath, FileMode.Create, FileAccess.ReadWrite);
}
lstContents.Add(reaponseStream.Current); //加入链表
if (lstContents.Count() >= 20) //每个包1M，20M为一个集合，一起写入数据。
{
lstContents.OrderBy(c => c.Block).ToList().ForEach(c => c.Content.WriteTo(fs));
lstContents.Clear();
}
}
}
}
fs?.Close(); //释放文件流
if (!result.IsSuccessful && !string.IsNullOrEmpty(savePath) && File.Exists(savePath)) //如果传输不成功，那么久删除该文件
{
File.Delete(savePath);
}
}
catch (Exception ex)
{
if (cancellationToken.IsCancellationRequested)
{
fs?.Close();//释放文件流
result.IsSuccessful = false;
result.Message = $"用户取消下载。已完成下载【{lstSuccFiles.Count}/{fileNames.Count}】，耗时：{DateTime.Now - startTime}";
}
else
{
result.Message = $"文件传输发生异常：{ex.Message}";
}
}
finally
{
fs?.Dispose();
}
result.Tag = fileNames.Except(lstSuccFiles).ToList();//获取失败文件集合
//关闭通信、并返回结果
return(await channel?.ShutdownAsync().ContinueWith(t => result));
}
/// <summary>
/// 文件上传
/// </summary>
/// <param name="filesPath">文件路径</param>
/// <param name="mark">标记</param>
/// <param name="cancellationToken">异步取消命令</param>
/// <returns>下载任务（是否成功、原因、成功的文件名）</returns>
public static async Task <TransferResult <List <string> > > FileUpload(List <string> filesPath, string mark, System.Threading.CancellationToken cancellationToken = new System.Threading.CancellationToken())
{
var result = new TransferResult <List <string> > {
Message = "没有文件需要下载"
};
if (filesPath.Count == 0)
{
return(await Task.Run(() => result));//没有文件需要下载
}
result.Message = "未能连接到服务器。";
var lstSuccFiles = new List <string>();//传输成功的文件
int chunkSize = 1024 * 1024;
byte[] buffer = new byte[chunkSize]; //每次发送的大小
FileStream fs = null; //文件流
Channel channel = null; //申明通信频道
GrpcService.FileTransfer.FileTransferClient client = null;
DateTime startTime = DateTime.Now;
try
{
(channel, client) = GetClient();
using (var stream = client.FileUpload())//连接上传文件的客户端
{
//reply.Block数字的含义是服务器和客户端约定的
foreach (var filePath in filesPath)//遍历集合
{
if (cancellationToken.IsCancellationRequested)
{
break;//取消了传输
}
FileReply reply = new FileReply()
{
FileName = Path.GetFileName(filePath),
Mark = mark
};
if (!File.Exists(filePath)) //文件不存在，继续下一轮的发送
{
Console.WriteLine($"文件不存在：{filePath}"); //写入日志
continue;
}
fs = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read, chunkSize, useAsync: true);
int readTimes = 0;
while (true)
{
if (cancellationToken.IsCancellationRequested)
{
reply.Block = -1; //取消了传输
reply.Content = Google.Protobuf.ByteString.Empty;
await stream.RequestStream.WriteAsync(reply); //发送取消传输的命令
break; //取消了传输
}
int readSize = fs.Read(buffer, 0, buffer.Length); //读取数据
if (readSize > 0)
{
reply.Block = ++readTimes;//更新标记，发送数据
reply.Content = Google.Protobuf.ByteString.CopyFrom(buffer, 0, readSize);
await stream.RequestStream.WriteAsync(reply);
}
else
{
Console.WriteLine($"完成文件【{filePath}】的上传。");
reply.Block = 0; //传送本次文件发送结束的标记
reply.Content = Google.Protobuf.ByteString.Empty;
await stream.RequestStream.WriteAsync(reply); //发送结束标记
//等待服务器回传
await stream.ResponseStream.MoveNext(cancellationToken);
if (stream.ResponseStream.Current != null && stream.ResponseStream.Current.Mark == mark)
{
lstSuccFiles.Add(filePath); //记录成功的文件
}
break; //发送下一个文件
}
}
fs?.Close();
}
if (!cancellationToken.IsCancellationRequested)
{
result.IsSuccessful = true;
result.Message = $"完成文件上传。共计【{lstSuccFiles.Count}/{filesPath.Count}】，耗时:{DateTime.Now - startTime}";
await stream.RequestStream.WriteAsync(new FileReply
{
Block = -2, //传输结束
Mark = mark
}); //发送结束标记
}
}
}
catch (Exception ex)
{
if (cancellationToken.IsCancellationRequested)
{
fs?.Close();//释放文件流
result.IsSuccessful = false;
result.Message = $"用户取消了上传文件。已完成【{lstSuccFiles.Count}/{filesPath.Count}】，耗时:{DateTime.Now - startTime}";
}
else
{
result.Message = $"文件上传发生异常({ex.GetType()})：{ex.Message}";
}
}
finally
{
fs?.Dispose();
}
Console.WriteLine(result.Message);
result.Tag = lstSuccFiles;
//关闭通信、并返回结果
return(await channel?.ShutdownAsync().ContinueWith(t => result));
}