How Do `async` and `await` Work in Async Programming Without Spawning Background Threads?

In the asynchronous programming

and understanding async await Many developers are confused about the work mechanism of

and

in asynchronous programming. To understand the mystery of their usage, we will explore their mechanisms and show the difference between them and generate background threads. async await Clarifying

and

Usage async await Your example emphasizes the use of and

in the "Button1_click" incident. Although this method is marked as is very important, this is not the same as generating background threads. Instead, asynchronous programming uses a state machine managed by the compiler in the background.

async In your code, after starting "DOSOMETHINGASYNC ()", the code continues to perform operations that are not related to the task. The "Access" variable holds the task that will end up. When reaching the "AWAIT Access" statement, the code is suspended and released the current thread. await async Understand the background execution

In contrast to your assumptions, "DOSOMETHINGASYNC ()" will not be executed on the background thread. It uses the current thread and starts the dormant operation. After completion, the state machine resumes execution and allows continuing to continue executing "Button1_CLICK".

A more comprehensive asynchronous example

In order to provide a clearer understanding, please consider the following example examples:

In this scene:

"MyMethodasync ()" starts "LongruningOperationasync ()".

public async Task MyMethodAsync()
{
    Task<int> longRunningTask = LongRunningOperationAsync();
    // 这里可以进行独立的工作...

    // 等待长时间运行的任务
    int result = await longRunningTask;
    // 使用结果...
}

public async Task<int> LongRunningOperationAsync()
{
    await Task.Delay(1000); // 1秒延迟
    return 1;
}

Executive independent work allows the main thread to continue.

When encountering "AWait Longrunningtask", the main thread will release and execute the suspension.

1. If "LongRunningOperationasync ()" is not completed, a thread in the thread pool will restore "MyMethodasync ()" and continue to execute after the task is completed.
2. If "LongRunningOperationasync ()" is completed, the results are available immediately. "MyMethodasync ()" continues to be executed on the same thread.
This example demonstrates how asynchronous programming promotes easy writing and efficient code to avoid blocking operations and ensure smooth execution processes.

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