C# Dynamic array

I want an array to contain strings, floats and ints that can be accessed via a index key.

I have an example in Lua how you would do but I don't know how you do it in

bookArray = {];
bookArray[1] = 
{
    Name = "Book 1";
    Price = 50;
    WPP = 374;
    Pages = 42;
}