How does Asynchronous tasks Async/Await work in .NET?

Asynchronous tasks Async/Await (Photo Credit — ChatGPT)

Modern .NET applications need to perform many operations that take time, such as reading files, calling APIs, or querying databases. If these operations run synchronously, they block the current thread, making the application slow or unresponsive.

This is where async and await come in.

What is Asynchronous Programming?

Asynchronous programming allows your application to start a task, continue doing other work, and return when the task is complete instead of waiting.

Synchronous Flow

Start
  │
  ▼
Call Database
  │
  ▼
Wait...
  │
  ▼
Receive Data
  │
  ▼
Continue

The thread remains blocked until the operation finishes.

Asynchronous Flow

Start
  │
  ▼
Call Database
  │
  ├────────────► Continue Other Work
  │
  ▼
Database Completes
  │
  ▼
Resume Execution

The thread is free while waiting for the operation to complete.

What is async?

The async keyword tells the compiler that a method contains asynchronous operations.

public async Task GetDataAsync()
{
    // asynchronous code
}