void SaveToStream(
    Stream stream
)

Sub SaveToStream(
    stream As Stream
)

using System.IO;
using DevExpress.ExpressApp;
using DevExpress.ExpressApp.Actions;
using DevExpress.Persistent.Base;
using DevExpress.Persistent.BaseImpl;
using MainDemo.Module.BusinessObjects;
// ...
public class UpdatePortfolioController : ObjectViewController<DetailView, Resume> {
    public UpdatePortfolioController() {
        SimpleAction updatePortfolioAction = new SimpleAction(this, "UpdatePortfolio", PredefinedCategory.Edit);
        updatePortfolioAction.SelectionDependencyType = SelectionDependencyType.RequireSingleObject;
        updatePortfolioAction.Execute += updatePortfolioAction_Execute;
    }
    private void updatePortfolioAction_Execute(object sender, SimpleActionExecuteEventArgs e) {
        FileData currentFile = ViewCurrentObject.File;
        if(currentFile != null && !currentFile.IsEmpty) {
            FileData fileCopy = ObjectSpace.CreateObject<FileData>();
            using(var stream = new MemoryStream()) {
                currentFile.SaveToStream(stream);
                stream.Position = 0;
                fileCopy.LoadFromStream(currentFile.FileName, stream);
            }
            PortfolioFileData portfolio = ObjectSpace.CreateObject<PortfolioFileData>();
            portfolio.File = fileCopy;
            ViewCurrentObject.Portfolio.Add(portfolio);
            ObjectSpace.CommitChanges();
        }
    }
}