MemoryStream.Position or MemoryStream.Seek does not work (Silverlight)

问题

I have a memorystream in a silverlight app. I have to copy this memorystream to a filestream object. If I call:

memoryStream.Position = 0;
memoryStream.Seek(0,SeekOrigin.Begin);

It does not work, I debug the application, check the properties of the memorystream, and the position still points to the end of the file. Any clues?

回答1:

Is it possible that another of your properties is being triggered in the debugger, and reading through the stream?

Rather than using the debugger, what happens if you log (or show on a message box):

Log("Position = " + stream.Position);
stream.Position = 0;
Log("Position = " + stream.Position);

Does that show the same non-zero number twice? I find it hard to believe that MemoryStream is that broken.

Btw, a simpler way of using MemoryStream for copying than manually copying everything is to call WriteTo with the FileStream as an argument.

来源：https://stackoverflow.com/questions/1899349/memorystream-position-or-memorystream-seek-does-not-work-silverlight