（1）添加一個類；（記住，不是添加一個窗體）

（2）添加命名空間，using system.windows;

(3)繼承window

（4）寫代碼

using System.Windows;
using System.Windows.Controls;

namespace 只使用代碼創建窗體
{
    class Windows1:Window
    {
        private Button button1;

        public Windows1()
        {
            Init();
        }
        void Init()
        {
            
 
this.Title = "只使用代碼創建的窗體";
            this.Height = 600;
            this.Width = 600;
            this.Top = 100;
            button1 = new Button();
            button1.Content = "請點擊我";
            button1.Margin = new Thickness(10);
            button1.Padding = new Thickness(10);
            button1.Click 
 
+= button1_click;
            this.AddChild(button1);
        }
        private void button1_click(object sensor,RoutedEventArgs e)
        {
            button1.Content = "已經被點擊";
        }
    }
}

效果

只使用代碼創建窗口