新的 C# await 功能有什么作用? [英] What's the new C# await feature do?

问题描述

谁能解释一下 await 函数的作用?

Can anyone explain what the await function does?

推荐答案

他们只是 昨天在 PDC 上谈到了这个！

Await 与 .NET 中的任务(并行编程)结合使用.这是 .NET 下一版本中引入的关键字.它或多或少让您暂停"方法的执行以等待任务完成执行.下面是一个简单的例子:

Await is used in conjunction with Tasks (parallel programming) in .NET. It's a keyword being introduced in the next version of .NET. It more or less lets you "pause" the execution of a method to wait for the Task to complete execution. Here's a brief example:

//create and run a new task  
Task<DataTable> dataTask = new Task<DataTable>(SomeCrazyDatabaseOperation);

//run some other code immediately after this task is started and running  
ShowLoaderControl();  
StartStoryboard();

//this will actually "pause" the code execution until the task completes.  It doesn't lock the thread, but rather waits for the result, similar to an async callback  
// please so also note, that the task needs to be started before it can be awaited. Otherwise it will never return
dataTask.Start();
DataTable table = await dataTask;

//Now we can perform operations on the Task result, as if we're executing code after the async operation completed  
listBoxControl.DataContext = table;  
StopStoryboard();  
HideLoaderControl();

这篇关于新的 C# await 功能有什么作用?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！