When and How Should You Use Async and Await in C#?

The timing and method of the use of and

async await

Understand Async and AWAIT

In C#,

and

are powerful keywords. They enhance the readability of the code and promote the execution of asynchronous tasks. Using them is not the same as creating background threads, because they use a different mechanism called asynchronous state machine. async await Example code details

Let's analyze the code fragments provided to demonstrate the work method of and

:

async await Behavioral explanation

private async void button1_Click(object sender, EventArgs e)
{
    Task<int> access = DoSomethingAsync();
    // 此处执行与任务无关的逻辑

    int a = 1; // 立即执行，因为它不依赖于 DoSomethingAsync()

    int x = await access; // 等待 DoSomethingAsync() 完成
}

async Task<int> DoSomethingAsync()
{
    await Task.Delay(5000); // 使线程休眠 5 秒
    return 1;
}

The method is marked as to enable its asynchronous execution.

is an asynchronous task that will not block the main thread.
1. button1_Click When running in the background, you can perform independent logic. async
will cause the execution of
2. until DoSomethingAsync() is completed.
3. Once is completed, the main thread will resume execution and assign the results of DoSomethingAsync() to
.
4. await access; button1_Click DoSomethingAsync() and
The mechanism
5. DoSomethingAsync() await When using and x, the compiler generates an asynchronous state machine. The mounting and recovery of this state machine management task allows asynchronous operations to write and perform asynchronous operations in a simplified manner.

Async and AWAIT's advantages

async await Improving code readability

Prevent the main thread of the block

async Enhanced UI's response ability await

The above is the detailed content of When and How Should You Use Async and Await in C#?. For more information, please follow other related articles on the PHP Chinese website!