Introduction
ASP.NET is a popular programming language used for building web applications. It provides a framework for developing dynamic websites, web services, and web applications. In this article, we will explore how to stream an IAsyncEnumerable on a nested property in ASP.NET Core.
Understanding IAsyncEnumerable
IAsyncEnumerable is a new interface introduced in C# 8.0 and .NET Core 3.0. It allows you to asynchronously iterate over a collection of data. It is similar to IEnumerable, but it supports asynchronous operations.
Streaming an IAsyncEnumerable on a Nested Property
Let's say we have a class called “Person” with a nested property called “Addresses”. The “Addresses” property is a collection of addresses associated with a person. We want to stream the addresses asynchronously using IAsyncEnumerable.
public class Person
{
public string Name { get; set; }
public IEnumerable Addresses { get; set; }
}
public class Address
{
public string Street { get; set; }
public string City { get; set; }
}
To stream the addresses asynchronously, we can use the “yield return” statement along with the “await Task.Yield()” method. This allows us to yield each address one by one without blocking the main thread.
public async IAsyncEnumerable StreamAddressesAsync(Person person)
{
foreach (var address in person.Addresses)
{
await Task.Yield();
yield return address;
}
}
Now, we can use the “StreamAddressesAsync” method to stream the addresses asynchronously. Here's an example:
public async Task StreamAddresses()
{
var person = new Person
{
Name = "John Doe",
Addresses = new List
{
new Address { Street = "123 Main St", City = "New York" },
new Address { Street = "456 Elm St", City = "Los Angeles" },
new Address { Street = "789 Oak St", City = "Chicago" }
}
};
await foreach (var address in StreamAddressesAsync(person))
{
// Do something with each address
}
return Ok();
}
In the above example, we create a new instance of the “Person” class with some addresses. We then use the “await foreach” statement to iterate over the addresses asynchronously. Inside the loop, you can perform any desired operations with each address.
Conclusion
In this article, we have learned how to stream an IAsyncEnumerable on a nested property in ASP.NET Core. By using the “yield return” statement and the “await Task.Yield()” method, we can asynchronously iterate over a collection of data without blocking the main thread. This can be useful when dealing with large datasets or when you want to perform operations on each item as it becomes available.
