13 Asynchronous Programming dotNet1.0 BeginXXX/EndXXX dotNet2.0 Event-Based Asynchronous Programming Asynchronous Component Pattern XXXCompleted事件/XXXAsync dotNet4.5 Task-Based Asynchronous Programming:TAP 基于dotNet4.0中的Task类型 使用编译器时特性 async和await 异常处理 取消