(40)Take advantage of .NET 4.5 async constructs

招数40：

利用.NET 4.5异步结构

With the arrival of .NET 4.5, writing async code correctly is easier than ever. Like any tool, it should be only applied where it makes most sense – in web use-cases this usually revolves around I/O operations (i.e. reading from disk, any network operation, database operations, or calls to web services).

随着.NET 4.5的到来，正确地编写异步代码比以往更容易。与其他工具一样，它应该只运用在最有意义的地方 - 在网络用例上这通常围绕着I/O操作（即：从磁盘读取，一些网络操作，数据库操作，或调用Web服务）。