.NET Object Spy and InvokeRemote

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using Bds.Inject;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Reflection;
using System.IO;

namespace Bds.ObjectSpy
{
    public partial class MainForm : Form
    {
        #region Win32 API Declarations

        [StructLayout(LayoutKind.Sequential)]
        public struct RECT
        {
            public int Left;
            public int Top;
            public int Right;
            public int Bottom;
        }
        
        [StructLayout(LayoutKind.Sequential)]
        public struct POINT
        {
            public int X;
            public int Y;

            #region Helper methods

            public POINT(int x, int y)
            {
                this.X = x;
                this.Y = y;
            }

            public static implicit operator System.Drawing.Point(POINT p)
            {
                return new System.Drawing.Point(p.X, p.Y);
            }

            public static implicit operator POINT(System.Drawing.Point p)
            {
                return new POINT(p.X, p.Y);
            }

            #endregion
        }

        const int DSTINVERT = 0x00550009;

        [DllImport("gdi32.dll")]
        static extern bool PatBlt(IntPtr hdc, int nXLeft, int nYLeft, int nWidth, int nHeight, uint dwRop);

        [DllImport("user32.dll")]
        static extern IntPtr WindowFromPoint(POINT Point);

        [DllImport("user32.dll")]
        static extern int GetWindowText(int hWnd, StringBuilder text, int count);

        [DllImport("user32.dll")]
        static extern IntPtr GetWindowDC(IntPtr hWnd);

        [DllImport("user32.dll")]
        static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);
        
        [DllImport("user32.dll")]
        static extern bool OffsetRect(ref RECT lprc, int dx, int dy);

        [DllImport("user32.dll")]
        static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName, int nMaxCount);

        [DllImport("user32.dll")]
        static extern uint GetWindowThreadProcessId(IntPtr hWnd, out int lpdwProcessId);

        #endregion

        bool _dragging;
        IntPtr _hWndCurrent;
        ContextMenuStrip _contextMenu;
        ToolStripMenuItem _browse;
        ToolStripMenuItem _cancel;
        Image _imgAppCross;
        Image _imgApp;
        Cursor _curCross;

        public MainForm()
        {
            InitializeComponent();

            Assembly assembly = Assembly.GetExecutingAssembly();
            _imgAppCross = Image.FromStream(assembly.GetManifestResourceStream("Bds.ObjectSpy.app_cross.bmp"));
            _imgApp = Image.FromStream(assembly.GetManifestResourceStream("Bds.ObjectSpy.app.bmp"));
            _curCross = new Cursor(assembly.GetManifestResourceStream("Bds.ObjectSpy.cross.cur"));

            dragPictureBox.Image = _imgAppCross;
            
            _browse = new ToolStripMenuItem("Inject Object Browser");
            _cancel = new ToolStripMenuItem("Cancel");
            _contextMenu = new ContextMenuStrip();
            _contextMenu.Items.Add(_browse);
            _contextMenu.Items.Add(_cancel);
            _browse.Click += new EventHandler(Browse_Click);
            _contextMenu.Closed += new ToolStripDropDownClosedEventHandler(ContextMenu_Closed);
        }

        private void DrawRevFrame(IntPtr hWnd)
        {
            if (hWnd == IntPtr.Zero)
                return;

            IntPtr hdc = GetWindowDC(hWnd);
            RECT rect;
            GetWindowRect(hWnd, out rect);
            OffsetRect(ref rect, -rect.Left, -rect.Top);

            const int frameWidth = 3;

            PatBlt(hdc, rect.Left, rect.Top, rect.Right - rect.Left, frameWidth, DSTINVERT);
            PatBlt(hdc, rect.Left, rect.Bottom - frameWidth, frameWidth,
                -(rect.Bottom - rect.Top - 2 * frameWidth), DSTINVERT);
            PatBlt(hdc, rect.Right - frameWidth, rect.Top + frameWidth, frameWidth,
                rect.Bottom - rect.Top - 2 * frameWidth, DSTINVERT);
            PatBlt(hdc, rect.Right, rect.Bottom - frameWidth, -(rect.Right - rect.Left),
                frameWidth, DSTINVERT);
        }

        private string GetWindowText(IntPtr hWnd)
        {
            StringBuilder text = new StringBuilder(256);
            if (GetWindowText(hWnd.ToInt32(), text, text.Capacity) > 0)
            {
                return text.ToString();
            }

            return String.Empty;
        }

        private string GetClassName(IntPtr hWnd)
        {
            StringBuilder className = new StringBuilder(100);
            if (GetClassName(hWnd, className, className.Capacity) > 0)
            {
                return className.ToString();
            }

            return String.Empty;
        }
        
        /*private bool IsManaged(IntPtr hWnd)
        {
            int procId;
            GetWindowThreadProcessId(hWnd, out procId);
            Process proc = Process.GetProcessById(procId);
            foreach (ProcessModule procModule in proc.Modules)
            {
                if (procModule.ModuleName == "mscorlib.dll" || procModule.ModuleName == "mscorlib.ni.dll")
                {
                    return true;
                }
            }

            return false;
        }*/

        private string GetApplication(IntPtr hWnd)
        {
            int procId;
            GetWindowThreadProcessId(hWnd, out procId);
            Process proc = Process.GetProcessById(procId);
            return proc.MainModule.ModuleName;
        }

        private void dragPictureBox_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                _dragging = true;
                this.Cursor = _curCross;
                dragPictureBox.Image = _imgApp;
            }
        }

        private void dragPictureBox_MouseUp(object sender, MouseEventArgs e)
        {
            if (_dragging)
            {
                _dragging = false;
                this.Cursor = Cursors.Default;
                if (_hWndCurrent != IntPtr.Zero)
                {
                    DrawRevFrame(_hWndCurrent);
                    _contextMenu.Show(MousePosition);
                    _hWndCurrent = IntPtr.Zero;
                    // The image in the dragPictureBox will be restored when the context menu is closed
                }
                else
                {
                    dragPictureBox.Image = _imgAppCross;
                }
            }
        }

        private void dragPictureBox_MouseMove(object sender, MouseEventArgs e)
        {
            if (_dragging)
            {
                IntPtr hWnd = WindowFromPoint(MousePosition);
                if (hWnd == dragPictureBox.Handle)
                {
                    // Drawing a border around the dragPictureBox (where we start
                    // dragging) doesn't look nice, so we ignore this window
                    hWnd = IntPtr.Zero;
                }

                if (hWnd != _hWndCurrent)
                {
                    if (_hWndCurrent != null)
                    {
                        DrawRevFrame(_hWndCurrent);
                    }
                    DrawRevFrame(hWnd);
                    _hWndCurrent = hWnd;
                }

                if (hWnd != IntPtr.Zero)
                {
                    txtWindowHandle.Text = hWnd.ToString();
                    txtWindowText.Text = GetWindowText(hWnd);
                    txtClassName.Text = GetClassName(hWnd);
                    txtApplication.Text = GetApplication(hWnd);
                }
                else
                {
                    txtWindowHandle.Text = String.Empty;
                    txtWindowText.Text = String.Empty;
                    txtClassName.Text = String.Empty;
                    txtApplication.Text = String.Empty;
                }
            }
        }

        void ContextMenu_Closed(object sender, ToolStripDropDownClosedEventArgs e)
        {
            dragPictureBox.Image = _imgAppCross;
        }

        void Browse_Click(object sender, EventArgs e)
        {
            IntPtr hWnd = new IntPtr(UInt32.Parse(txtWindowHandle.Text));
            Injector.InvokeRemote(hWnd, "ObjectSpyLib.dll", "Bds.ObjectSpy.ObjectSpyForm", "ShowBrowser", new object[] { hWnd });
        }

        private void aboutLinkLabel_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            MessageBox.Show(String.Format("{0}\nVersion {1}\n\nWritten by Bjarne Dam S�rensen", this.Text, Application.ProductVersion.ToString()),
                "About " + this.Text, MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
    }
}