using System;
using System.Runtime.InteropServices;
using System.Windows;
using System.Windows.Input;
using System.Windows.Interop;


         public partial class MainWindow : Window
            {
                public MainWindow()
                {
                    InitializeComponent();
                }
        
                private void Image_MouseDown(object sender, MouseButtonEventArgs e)
                {
                    MessageBox.Show("image");
        
                }
        
                private void TextBlock_PreviewMouseDown(object sender, MouseButtonEventArgs e)
                {
                    MessageBox.Show("textblock");
                }
                protected override void OnSourceInitialized(EventArgs e)
                {
                    base.OnSourceInitialized(e);
                    var hwnd = new WindowInteropHelper(this).Handle;
                    WindowsServices.SetWindowExTransparent(hwnd);
                }
            }
            public static class WindowsServices
            {
                const int WS_EX_TRANSPARENT = 0x00000020;
                const int GWL_EXSTYLE = (-20);
        
                [DllImport("user32.dll")]
                static extern int GetWindowLong(IntPtr hwnd, int index);
        
                [DllImport("user32.dll")]
                static extern int SetWindowLong(IntPtr hwnd, int index, int newStyle);
        
                public static void SetWindowExTransparent(IntPtr hwnd)
                {
                    var extendedStyle = GetWindowLong(hwnd, GWL_EXSTYLE);
                    SetWindowLong(hwnd, GWL_EXSTYLE, extendedStyle | WS_EX_TRANSPARENT);
                }
            }