考虑我有以下片段:
public void Store(Stream s, object t)
{
var serializer = new DataContractSerializer(target.GetType(),
new DataContractSerializerSettings
{
PreserveObjectReferences = true
});
serializer.WriteObject(s, target);
}
其中
s
是 只写 并且 不支持查找。
有什么方法可以获取由
WriteObject
写入流的字节数吗?我知道我可以通过以下方式做到这一点:
using (var memStream = new MemoryStream())
{
serializer.WriteObject(serializer, target);
Debug.WriteLine(memStream.Length);
memStream.CopyTo(s);
}
但我想知道是否可以避免
CopyTo
- 物体相当巨大。
编辑: 我刚刚想出了一个想法:我可以创建一个包装器来计算写入的字节数。这是最好的解决方案,但也许还有另一种方法。
完成
我已经实现了一个包装器:https://github.com/pwasiewicz/counted-stream - 也许它对某人有用。
谢谢!
我制作的包装器的示例实现:
public class CountedStream : Stream
{
private readonly Stream stream;
public CountedStream(Stream stream)
{
if (stream == null) throw new ArgumentNullException("stream");
this.stream = stream;
}
public long WrittenBytes { get; private set; }
public override void Flush()
{
this.stream.Flush();
}
public override int Read(byte[] buffer, int offset, int count)
{
return this.stream.Read(buffer, offset, count);
}
public override long Seek(long offset, SeekOrigin origin)
{
return this.stream.Seek(offset, origin);
}
public override void SetLength(long value)
{
this.stream.SetLength(value);
}
public override void Write(byte[] buffer, int offset, int count)
{
if (buffer.Length >= offset + count)
throw new ArgumentException("Count exceeds buffer size");
this.stream.Write(buffer, offset, count);
this.WrittenBytes += count;
}
public override bool CanRead
{
get { return this.stream.CanRead; }
}
public override bool CanSeek
{
get { return this.stream.CanSeek; }
}
public override bool CanWrite
{
get { return this.stream.CanWrite; }
}
public override long Length
{
get { return this.stream.Length; }
}
public override bool CanTimeout
{
get { return this.stream.CanTimeout; }
}
public override long Position
{
get { return this.stream.Position; }
set { this.stream.Position = value; }
}
}
可与:
一起使用Stream.Position
希望我能理解你,这会对你有所帮助。