我正在尝试通过流从cloudBlob下载文件。我引用这篇文章CloudBlob
这是下载Blob的代码
public Stream DownloadBlobAsStream(CloudStorageAccount account, string blobUri)
{
Stream mem = new MemoryStream();
CloudBlobClient blobclient = account.CreateCloudBlobClient();
CloudBlockBlob blob = blobclient.GetBlockBlobReference(blobUri);
if (blob != null)
blob.DownloadToStream(mem);
return mem;
}
和将其转换为字节数组的代码
public static byte[] ReadFully(Stream input)
{
byte[] buffer = new byte[16 * 1024];
using (MemoryStream ms = new MemoryStream())
{
int read;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
return ms.ToArray();
}
}
但是我总是得到空值。以下是流文件的内容。
这有什么问题?请帮忙。
编辑
不允许在
ReadFully
方法中将Position设置为0,因此我将其放在DownloadBlobAsStream
中现在应该可以使用:
public Stream DownloadBlobAsStream(CloudStorageAccount account, string blobUri)
{
Stream mem = new MemoryStream();
CloudBlobClient blobclient = account.CreateCloudBlobClient();
CloudBlockBlob blob = blobclient.GetBlockBlobReference(blobUri);
if (blob != null)
blob.DownloadToStream(mem);
mem.Position = 0;
return mem;
}
最佳答案
您的问题是您的输入流指针设置为流的结尾(请参见屏幕快照,“长度”和“位置”都显示相同的值),这就是为什么在读取时始终获得null的原因。您需要使用 Stream.Position = 0 来设置输入流指针为0,如下所示:
public static byte[] ReadFully(Stream input)
{
byte[] buffer = new byte[16 * 1024];
input.Position = 0; // Add this line to set the input stream position to 0
using (MemoryStream ms = new MemoryStream())
{
int read;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
return ms.ToArray();
}
}
关于c# - CloudBlob.DownloadToStream返回null,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/10891857/