为什么WCF在Close()上读取EOF的输入流?

[ServiceContract, XmlSerializerFormat]
public interface IReplicationWebService
{
    [OperationContract]
    [WebInvoke(Method = "PUT", UriTemplate = "agents/{sourceName}/epoch/{guid}/{number}/{type}")]
    ReplayResult PutEpochFile(string sourceName, string guid, string number, string type, Stream stream);
}

在执行本合同时,我们从以下来源读取数据 stream

    public ReplayResult PutEpochFile(string sourceName, string guid, string number, string type, Stream inStream)
    {
        //Stuff snipped
        try
        {
            //Read from the stream and write to the file
        }
        catch (IOException ioe)
        {
            //IOException may mean no disk space
            try
            {
                inStream.Close();
            }
            // if instream caused the IOException, close may throw
            catch
            {
            }
            _logger.Debug(ioe.ToString());
            throw new FaultException<IOException>(ioe, new FaultReason(ioe.Message), new FaultCode("IO"));
        }
    }

为了测试这一点,我将向没有足够空间的服务器发送一个100GB的文件。正如预期的那样,这会抛出一个异常,但调用 inStream.Close() Close() System.ServiceModel.Channels.DrainOnCloseStream.Close() Byte[]

Close

在这条小溪上。如果是这样的话,我想解释一下原因。但更重要的是,如果有人能向我解释原因,我将不胜感激