Creating a Button

Question

Following program is in a book. It is executing. But I couldn't understand the logic because Text on the Button should come after creating a Button. Problem is highlighted.

using System;
using System.Windows.Forms;
using System.Drawing;

public class WindowWithButton : Form
{
Button button1 = new Button();

public WindowWithButton()
{
this.Size = new Size(300, 300);

this.Text = "Window Object With Button";
button1.Text = "Press";

this.Controls.AddRange(new System.Windows.Forms.Control[] { this.button1 });// Creating a Button

this.button1.Location = new Point(100, 50);

}

public static void Main()
{
Application.Run(new WindowWithButton());
}
}