Creating a page in C#

For clarity, the following code shows how the same thing would look in C#:

public class MainPage : ContentPage
{
}

A page is a class that inherits from the Xamarin.Forms.ContentPage. This class is autogenerated for you if you create a XAML page, but if you go code-only, then you will need to define it yourself. 

Let's create the same control hierarchy as the XAML page we defined earlier using the following code:

var page = new MainPage();

var stacklayout = new StackLayout();
stacklayout.Children.Add(
    new Label()
    {
        Text = "Welcome to Xamarin.Forms"
    });

page.Content = stacklayout;

The first statement creates a page. You could, in theory, create a new page directly of the ContentPage type, but this would prohibit you from writing any code behind it. For this reason, it's a good practice to subclass each page that you are planning to create.

The block following this first statement creates the StackLayout control that contains the Label control that is added to the Children collection.

Finally, we need to assign the StackLayout to the Content property of the page.