Reading the same file with several different streams in Qt

问题

Is it possible to read a file using multiple streams to access different portions of data in it at the same time, using Qt?

回答1:

Note that a stream (QTextStream / QDataStream) in Qt doesn't handle the position in the underlying device. A stream class is only a wrapper for easier parsing of the binary data within the device (QFile instance).

So two streams for the same device (QFile) will not work.

You can, however, have multiple devices (QFile) for the same underlying file, and each of them can then be read using another stream instance.

来源：https://stackoverflow.com/questions/11710598/reading-the-same-file-with-several-different-streams-in-qt