Dynamic syntax in C#

Question

Recently, I've come across C# examples that use a syntax that looks like the following:

var result = new { prop1 = "hello", prop2 = "world", prop3 = "." };

I really like it. It looks like JSON a bit. However, I don't know what this syntax is called. For that reason, I'm not sure how to learn more about it. I'm really interested in trying to figure out how to define arrays of objects within a result. For instance, what if I wanted to return an array of items for prop3? What would that look like? What is this syntax called?

Answer 1

This is referred to as Anonymous Types in C#.

To return an array, you can simply inline it:

var result = new { prop1 = "hello", prop2 = "world", prop3 = new int[] {1,2,3} };

Or declare it beforehand and use it:

int[] array = new int[] {1,2,3};
var result = new { prop1 = "hello", prop2 = "world", prop3 = array};

Answer 2

it's called anonymous types. For returning an array of objects in prop3 you would write

var result = new { prop1 = "hello", prop2 = "world", prop3 = new[] { "h", "e", "l", "l", "o" } };

I'm using strings but is the same for any type of object:

var result = new { prop1 = "hello", prop2 = "world", prop3 = new[] { new YourType(), new YourType(), new YourType() } };

Note that the type of the objects in the array is not necessary in the declaration of the array; you don't need to write new YourType[], the compiler don't need it and IMO it's cleaner to simply use new[]