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copied!<p>UPDATE: This approach works against NuGet current, but relies in an anomaly in the <code>InCallscope</code> implementation which has been fixed in the current Unstable NuGet packages. I'll be tweaking this answer in a few days to reflect the best approach after some mulling over. NB the high level way of structuring stuff will stay pretty much identical, just the exact details of the <code>Bind<DbContext>()</code> scoping will work. (Hint: <code>CreateNamedScope</code> in unstable would work or one could set up the Command Handler as <code>DefinesNamedScope</code>. Reason I dont just do that is that I want to have something that composes/plays well with <code>InRequestScope</code>) </p> <hr> <p>I highly recommend reading the <code>Ninject.Extensions.NamedScope</code> integration tests (seriously, find them and read and re-read them)</p> <p>The <code>DbContext</code> <strong>is</strong> a Unit Of Work so no further wrapping is necessary.</p> <p>As you want to be able to have multiple 'requests' in flight and want to have a single Unit of Work shared between them, you need to:</p> <pre><code>Bind<DbContext>() .ToMethod( ctx => new DbContext( connectionStringName: ConfigurationUtility.GetConnectionString() )) .InCallScope(); </code></pre> <p>The <code>InCallScope()</code> means that:</p> <ol> <li>for a given object graph composed for a single <code>kernel.Get()</code> <strong>Call</strong> (hence In <em>Call</em> Scope), everyone that requires an <code>DbContext</code> will get the same instance.</li> <li>the <code>IDisposable</code>.<code>Dispose()</code> will be called when a <code>Kernel.Release()</code> happens for the root object (or a <code>Kernel.Components.Get<ICache>().Clear()</code> happens for the root if it is not <code>.InCallScope()</code>)</li> </ol> <p>There should be no reason to use <code>InNamedScope()</code> and <code>DefinesNamedScope()</code>; You don't have long-lived objects you're trying to exclude from the default pooling / parenting / grouping.</p> <p>If you do the above, you should be able to:</p> <pre><code>var command = kernel.Get<ICommand>(); try { command.Execute(); } finally { kernel.Components.Get<ICache>().Clear( command ); // Dispose of DbContext happens here } </code></pre> <p>The Command implementation looks like:</p> <pre><code>class Command : ICommand { readonly IAccountRepository _ar; readonly IBlockedIpRepository _br; readonly DbContext _ctx; public Command(IAccountRepository ar, IBlockedIpRepository br, DbContext ctx){ _ar = ar; _br = br; _ctx = ctx; } void ICommand.Execute(){ _ar.Insert(a); _br.Insert(b); _ctx.saveChanges(); } } </code></pre> <hr> <p>Note that in general, I avoid having an implicit Unit of Work in this way, and instead surface it's creation and <code>Disposal</code>. This makes a Command look like this:</p> <pre><code>class Command : ICommand { readonly IAccountService _as; readonly IBlockedIpService _bs; readonly Func<DbContext> _createContext; public Command(IAccountService @as, IBlockedIpServices bs, Func<DbContext> createContext){ _as = @as; _bs = bs; _createContext = createContext; } void ICommand.Execute(){ using(var ctx = _createContext()) { _ar.InsertA(ctx); _br.InsertB(ctx); ctx.saveChanges(); } } </code></pre> <p>This involves no usage of <code>.InCallScope()</code> on the <code>Bind<DbContext>()</code> (but does require the presence of <a href="https://github.com/ninject/ninject.extensions.factory/wiki" rel="nofollow"><code>Ninject.Extensions.Factory</code>'s <code>FactoryModule</code></a> to synthesize the <code>Func<DbContext></code> from a straightforward <code>Bind<DbContext>()</code>.</p>

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