当我尝试从 Amazon S3 下载一个大文件(大小为 2GB 的 zip 文件)时，它会抛出异常“流太长”。这就是我从 Amazon 读取此文件到流中的方式
var s3File = new S3FileInfo(Client, BucketName, ObjectKey);
var stream = s3File.OpenRead();
是否可以将文件内容读取成小块，然后在本地合并？
-艾伦-
最佳答案
public class BuketObjectResult
{
public bool Success { get; set; }
public long Size { get; set; }
}
public void GetBucketObjectData()
{
try
{
BuketObjectResult res = CheckFile();
//CHUNK Divide in small chunks eg : 2GB file : 20MB chunks
int chunkSize = (int)(res.Size / CHUNK);
if (!res.Success && (res.Size == 0 || chunkSize <= 0))
{
res.Success = false;
return ;
}
string fileName = "Your file name";
long startPostion = 0;
long endPosition = 0;
while (startPostion >= 0)
{
byte[] chunk = new byte[chunkSize];
endPosition = chunkSize + startPostion;
if (endPosition > res.Size) //to get rest of the file
endPosition = res.Size;
GetObjectRequest request = new GetObjectRequest
{
BucketName = "your bucket name",
Key = "your key",
ByteRange = new ByteRange(startPostion, endPosition)
};
using (GetObjectResponse response = s3client.GetObject(request))
using (Stream responseStream = response.ResponseStream)
using (FileStream fileStream = File.Open(fileName, FileMode.Append))
{
int readIndex = ReadChunk(responseStream, ref chunk);
startPostion += readIndex;
if (readIndex != 0)
{
fileStream.Write(chunk, 0, readIndex);
}
if (readIndex != chunk.Length) // We didn't read a full chunk: we're done (read only rest of the bytes)
break;
}
}
// Verify
FileInfo fi = new FileInfo(fileName);
if (fi.Length == res.Size)
{
res.Success = true;
}
}
catch (Exception e)
{
}
}
public BuketObjectResult CheckFile()
{
BuketObjectResult res = new BuketObjectResult() { Success = false};
try
{
ListObjectsRequest request = new ListObjectsRequest()
{
BucketName = "bucketName here ",
Delimiter = "/",
Prefix = "Location here"
};
ListObjectsResponse response = s3client.ListObjects(request);
if (response.S3Objects != null && response.S3Objects.Count > 0)
{
S3Object o = response.S3Objects.Where(x => x.Size != 0).FirstOrDefault();
if (o != null)
{
res.Success = true;
res.Size = o.Size;
}
}
}
catch (Exception e)
{
}
return res;
}
关于c# - Amazon S3 流太长，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37425732/