设置重试策略(Setting up a retry policy)

 只是快速，脱下袖口的答案。 
 
 如何使用.NET的Reactive Extensions（Rx） ？ 
 
 然后，您可以将存储库定义为： 
 
public interface IObservableRepository<T> where T : class
{
    IObservable<T> GetById(int id);
    IObservable<T> GetAll(Func<IQueryable<T>, IQueryable<T>> query);
    IObservable<Unit> InsertOnSubmit(T entity);
    IObservable<Unit> DeleteOnSubmit(T entity);
    IObservable<int> SubmitChanges();
}
 
 所有返回的observable都将包含单个值，但GetAll除外，它将具有零或更多。 
 
 Rx世界中的Unit类型void 。 这只是一种不需要定义非通用IObservable接口的方法。 
 
 然后你会这样查询： 
 
IObservableRepository<Foo> repo = ...;

var foos = repo.GetAll(ts => ts.Where(t => t.Bar == "Hello"));

foos.Subscribe(foo =>
{
    // Do something asynchronously with each `Foo`.
});
 
 提交可以这样做： 
 
var submit =
    foos
        .Select(foo => repo.InsertOnSubmit(foo)).ToArray()
        .Select(s => repo.SubmitChanges());

submit.Subscribe(result =>
{
    // handle the asynchronous result of submit.
});
 
 这都是基于尝试使存储库方法尽可能接近原始方法，但在Silverlight方面可能需要重构这样的事情： 
 
public interface IObservableRepository<T> where T : class
{
    IObservable<T> GetById(int id);
    IObservable<T[]> GetAll(Func<IQueryable<T>, IQueryable<T>> query);
    IObservable<int> Submit(T[] insertsOrUpdates);
    IObservable<int> Submit(T[] insertsOrUpdates, T[] deletes);
}
 
 现在提交会更好一些： 
 
repo.Submit(foos).Subscribe(result =>
{
    // Handle asynchronous result of submit;
});
 
 就像我说的那样，袖口。 :-) 

Just a quick, off the cuff answer.
 
How about using the Reactive Extensions for .NET (Rx)?
 
You could then define your repository as:
 
public interface IObservableRepository<T> where T : class
{
    IObservable<T> GetById(int id);
    IObservable<T> GetAll(Func<IQueryable<T>, IQueryable<T>> query);
    IObservable<Unit> InsertOnSubmit(T entity);
    IObservable<Unit> DeleteOnSubmit(T entity);
    IObservable<int> SubmitChanges();
}
 
All of the returned observables would contain single values, except for GetAll which would have zero or more.
 
The Unit type is void in the Rx world. It's just a way of not needing to define a non-generic IObservable interface.
 
You would then query like so:
 
IObservableRepository<Foo> repo = ...;

var foos = repo.GetAll(ts => ts.Where(t => t.Bar == "Hello"));

foos.Subscribe(foo =>
{
    // Do something asynchronously with each `Foo`.
});
 
And submit could be done like this:
 
var submit =
    foos
        .Select(foo => repo.InsertOnSubmit(foo)).ToArray()
        .Select(s => repo.SubmitChanges());

submit.Subscribe(result =>
{
    // handle the asynchronous result of submit.
});
 
This is all based on trying to keep the repository methods as close as possible to the original, but it may be worth refactoring on the Silverlight side to something like this:
 
public interface IObservableRepository<T> where T : class
{
    IObservable<T> GetById(int id);
    IObservable<T[]> GetAll(Func<IQueryable<T>, IQueryable<T>> query);
    IObservable<int> Submit(T[] insertsOrUpdates);
    IObservable<int> Submit(T[] insertsOrUpdates, T[] deletes);
}
 
Submit would be a bit nicer now:
 
repo.Submit(foos).Subscribe(result =>
{
    // Handle asynchronous result of submit;
});
 
Like I said, off the cuff. :-)