我正在尝试将一个对象序列化为 XML,但是我的对象是一个包含许多记录的通用列表,并导致序列化程序消耗大量内存。所以我尝试使用以下代码直接序列化为 GZipStream:
Dim formatter As XmlSerializer = XmlSerializerFactory.GetSerializerForType(_type)
Using _ms As New MemoryStream()
Using gzStream As New GZipStream(_ms, CompressionMode.Compress, True)
_ms.Position = 0
formatter.Serialize(gzStream, obj)
_ms.Position = 0
gzStream.Flush()
gzStream.Close()
End Using
_ms.Position = 0
Dim decompressData() As Byte
Using gzStream As New GZipStream(_ms, CompressionMode.Decompress)
ReDim decompressData(9000 - 1) 'this number doesn't matter, the data in my test sample is small
Dim Len As Integer = gzStream.Read(decompressData, 0, decompressData.Length)
End Using
End Using
The magic number in GZip header is not correct. Make sure you are passing in a GZip stream.
但是,当我尝试将数据读入 decompressData 数组时遇到了 InvalidDataException 。
当我首先序列化到单独的内存流然后压缩该流时,例如:
Dim formatter As XmlSerializer = XmlSerializerFactory.GetSerializerForType(_type)
Using _ms As New MemoryStream()
Dim uc_fileBytes() As Byte
Dim uc_len As Integer
Using _ms101 As New MemoryStream()
formatter.Serialize(_ms101, obj)
uc_fileBytes = _ms101.GetBuffer()
uc_len = _ms101.Length
End Using
Using gzStream As New GZipStream(_ms, CompressionMode.Compress, True)
_ms.Position = 0
gzStream.Write(uc_fileBytes, 0, uc_len)
gzStream.Flush()
gzStream.Close()
End Using
Dim decompressData() As Byte
Using gzStream As New GZipStream(_ms, CompressionMode.Decompress)
ReDim decompressData(9000 - 1)
Dim Len As Integer = gzStream.Read(decompressData, 0, decompressData.Length)
End Using
End Using
它工作正常,没有错误。但是为什么我直接序列化到 GZipStream 会失败呢?