http://blog.csdn.net/shihuan10430049/article/details/3734398

http://blogs.msdn.com/b/johan/archive/2006/11/15/are-you-getting-outofmemoryexceptions-when-uploading-large-files.aspx

http://blog.csdn.net/five3/article/details/7181521

c# Winform上传文件