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Hijacking another processes form

So, I have been asked to figure out a way to make a program containing sensitive data more secure since we have staff that go afk and put potentially put data at risk.
I have loaded up Visual Studio for C# and found a nice way to get process of the fore mentioned application. Then grab the main window and attach a panel of my very own. This panel will basically now be used like a blind covering the application when its not in use.
Now, I have a program running in system tray waiting for the sensitive data to come on screen and my little panel hijacks the entire window and now nothing can be seen.
My problem now is how ever, that whilst my panel is attacked the main window of the application i am trying to lock out seems to just crash. I am guessing that is because my panel and the application belong to different processes.
Anyway I could do with some advise here.
Here is my panels class.
class LockingPanel : System.Windows.Forms.Panel
{
private IntPtr prn;
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent);
public void SetParent(IntPtr parent)
{
prn = parent;
SetParent(this.Handle, prn);
}
public IntPtr GetParent() {
return prn;
}
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool GetWindowRect(IntPtr hWnd, ref RECT Rect);
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left; // x position of upper-left corner
public int Top; // y position of upper-left corner
public int Right; // x position of lower-right corner
public int Bottom; // y position of lower-right corner
}
public void FillParent()
{
RECT rtc = new RECT();
GetWindowRect(prn, ref rtc);
this.Location = new System.Drawing.Point(0, 0);
this.Size = new System.Drawing.Size(rtc.Right, rtc.Bottom);
}
Anybody got a better idea on how I can go about this, or at least make it so that my panel inst going to crash the application.

Windows screensaver in C# using WPF crashing during preview mode

I have just started to learn C# and am trying to write a screensaver. My App.xaml.cs contains the following code for when the /p argument is used:
else if (arg1 == "/p")
{
if (e.Args[1] == null)
{
System.Windows.Forms.MessageBox.Show("Invalid or missing window handle.");
System.Windows.Application.Current.Shutdown();
}
IntPtr previewHandle = new IntPtr(long.Parse(e.Args[1]));
System.Windows.Application.Current.Run(new MainWindow(previewHandle));
}
Then in my MainWindow.xaml.cs, this construct handles the preview call:
public MainWindow(IntPtr previewHandle)
{
App.Current.Properties["isPreviewMode"] = true;
App.Current.Properties["previewHandle"] = previewHandle;
InitializeComponent();
}
After this, it crashes. In my MainWindow.xaml I have Loaded="MainWindow_Loaded".
In MainWindows.xaml.cs this is MainWindow_Loaded:
private void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
if ((bool)App.Current.Properties["isPreviewMode"])
{
IntPtr myHandle = new WindowInteropHelper(this).Handle;
SetParent(myHandle, (IntPtr)App.Current.Properties["previewHandle"]);
SetWindowLong(myHandle, -16, new IntPtr(GetWindowLong(myHandle, -16) | 0x40000000));
Rectangle ParentRect;
GetClientRect((IntPtr)App.Current.Properties["previewHandle"], out ParentRect);
this.Top = ParentRect.X;
this.Left = ParentRect.Y;
this.Height = ParentRect.Height;
this.Width = ParentRect.Width;
}
ssimage.Source = new BitmapImage(new Uri("pack://application:,,,/Resources/EmbeddedImage.PNG"));
}
[DllImport("user32.dll")]
static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent);
[DllImport("user32.dll")]
static extern int SetWindowLong(IntPtr hWnd, int nIndex, IntPtr dwNewLong);
[DllImport("user32.dll", SetLastError = true)]
static extern int GetWindowLong(IntPtr hWnd, int nIndex);
[DllImport("user32.dll")]
static extern bool GetClientRect(IntPtr hWnd, out Rectangle lpRect);
I have other code in the App.xaml.cs to handle changing the images on a timer and other code in MainWindow.xaml.cs to handle mouse movement, clicks and keypresses. Everything works fine when running the screensaver normally. It is just the preview that fails. What am I doing wrong?

To my knowledge, WPF does not allow you to retarget the window handle, so performing screensaver previews in WPF using your technique is impossible.
However, there is a workaround: if you configure WPF to render to a bitmap target (see RenderTargetBitmap), you could then blit that bitmap onto the desired destination window handle - but this would involve an unholy mix of GDI and WPF and probably have awful runtime performance; I doubt it would be worth the effort.

What I ended up doing was using the WPF windows to display when the screensaver runs normally in full screen with /s. I created a new regular windows form previewForm.cs with a picturebox to use for the preview. That works fine and there is no performance issues. I assume the picturebox is using GDI.
This is my modified App.xaml.cs for handling the /p argument:
else if (arg1 == "/p")
{
if (e.Args[1] == null)
{
System.Windows.Forms.MessageBox.Show("Invalid or missing window handle.");
System.Windows.Application.Current.Shutdown();
}
IntPtr previewHandle = new IntPtr(long.Parse(e.Args[1]));
pw = new previewForm(previewHandle);
GetImages();
pw.Show();
}
and my previewForm.cs construct to handle the preview:
public previewForm(IntPtr previewHandle)
{
InitializeComponent();
IntPtr myHandle = this.Handle;
SetParent(myHandle, previewHandle);
SetWindowLong(myHandle, -16, new IntPtr(GetWindowLong(myHandle, -16) | 0x40000000));
Rectangle ParentRect;
GetClientRect(previewHandle, out ParentRect);
this.Size = ParentRect.Size;
this.pictureBox1.Size = ParentRect.Size;
this.Location = new Point(0, 0);
}
So I used a mix of a WPF form and a regular windows form to accomplish this. And the performance is fine. Only uses like 14-18MB of RAM and practically no CPU.

Position a small console window to the bottom left of the screen?

As the title says, I want to position it to the bottom left corner of the screen. Here's the code I have so far:
Console.WindowWidth = 50
Console.WindowHeight = 3
Console.BufferWidth = 50
Console.BufferHeight = 3
Console.BackgroundColor = ConsoleColor.Black
Console.ForegroundColor = ConsoleColor.DarkMagenta
Console.Title = "My Title"
Console.WriteLine("")
Console.Write(" Press any key to close this window ...")
Console.ReadKey()

Note: Despite their names, setting Console.WindowLeft and Console.WindowTop of the System.Console class does not change the window's position on screen.
Instead, they position the visible part of the window relative to the (potentially larger) window buffer - you cannot use type System.Console to change the position of console windows on the screen - you need to use the Windows API for that.
The following is code for a complete console application that positions its own window in the lower left corner of the screen, respecting the location of the taskbar.
Note:
It should work with multi-monitor setups - positioning the window on the specific monitor (display, screen) it is (mostly) being displayed on - but I haven't personally verified it.
Only Windows API functions are used via P/Invoke declarations, avoiding the need for referencing the WinForms assembly (System.Windows.Forms), which is not normally needed in console applications.
You'll see that a good portion of the code is devoted to P/Invoke signatures (declaration) for interfacing with the native Windows APIs; these were gratefully adapted from pinvoke.net
The actual code in the Main() method is short by comparison.
If you compile the code below from a console-application project in Visual Studio and run the resulting executable from a cmd.exe console window (Command Prompt), that console window should shift to the lower left corner of the (containing screen).
To verify the functionality while running from Visual Studio, place a breakpoint at the closing } and, when execution pauses, Alt-Tab to the console window to verify its position.
using System;
using System.Runtime.InteropServices; // To enable P/Invoke signatures.
public static class PositionConsoleWindowDemo
{
// P/Invoke declarations.
[DllImport("kernel32.dll")]
static extern IntPtr GetConsoleWindow();
[DllImport("user32.dll")]
static extern IntPtr MonitorFromWindow(IntPtr hwnd, uint dwFlags);
const int MONITOR_DEFAULTTOPRIMARY = 1;
[DllImport("user32.dll")]
static extern bool GetMonitorInfo(IntPtr hMonitor, ref MONITORINFO lpmi);
[StructLayout(LayoutKind.Sequential)]
struct MONITORINFO
{
public uint cbSize;
public RECT rcMonitor;
public RECT rcWork;
public uint dwFlags;
public static MONITORINFO Default
{
get { var inst= new MONITORINFO(); inst.cbSize = (uint)Marshal.SizeOf(inst); return inst; }
}
}
[StructLayout(LayoutKind.Sequential)]
struct RECT
{
public int Left, Top, Right, Bottom;
}
[StructLayout(LayoutKind.Sequential)]
struct POINT
{
public int x, y;
}
[DllImport("user32.dll", SetLastError = true)]
static extern bool GetWindowPlacement(IntPtr hWnd, ref WINDOWPLACEMENT lpwndpl);
[DllImport("user32.dll", SetLastError = true)]
static extern bool SetWindowPlacement(IntPtr hWnd, [In] ref WINDOWPLACEMENT lpwndpl);
const uint SW_RESTORE= 9;
[StructLayout(LayoutKind.Sequential)]
struct WINDOWPLACEMENT
{
public uint Length;
public uint Flags;
public uint ShowCmd;
public POINT MinPosition;
public POINT MaxPosition;
public RECT NormalPosition;
public static WINDOWPLACEMENT Default
{
get
{
var instance = new WINDOWPLACEMENT();
instance.Length = (uint) Marshal.SizeOf(instance);
return instance;
}
}
}
public static void Main()
{
// Get this console window's hWnd (window handle).
IntPtr hWnd = GetConsoleWindow();
// Get information about the monitor (display) that the window is (mostly) displayed on.
// The .rcWork field contains the monitor's work area, i.e., the usable space excluding
// the taskbar (and "application desktop toolbars" - see https://msdn.microsoft.com/en-us/library/windows/desktop/ms724947(v=vs.85).aspx)
var mi = MONITORINFO.Default;
GetMonitorInfo(MonitorFromWindow(hWnd, MONITOR_DEFAULTTOPRIMARY), ref mi);
// Get information about this window's current placement.
var wp = WINDOWPLACEMENT.Default;
GetWindowPlacement(hWnd, ref wp);
// Calculate the window's new position: lower left corner.
// !! Inexplicably, on W10, work-area coordinates (0,0) appear to be (7,7) pixels
// !! away from the true edge of the screen / taskbar.
int fudgeOffset = 7;
wp.NormalPosition = new RECT() {
Left = -fudgeOffset,
Top = mi.rcWork.Bottom - (wp.NormalPosition.Bottom - wp.NormalPosition.Top),
Right = (wp.NormalPosition.Right - wp.NormalPosition.Left),
Bottom = fudgeOffset + mi.rcWork.Bottom
};
// Place the window at the new position.
SetWindowPlacement(hWnd, ref wp);
}
}

You can use Console.WindowTop and Console.WindowWidth of the System.Console class to set the location of the console window.
Here is an example on MSDN
The BufferHeight and BufferWidth property gets/sets the number of rows and columns to be displayed.
WindowHeight and WindowWidth properties must always be less than BufferHeight and BufferWidth respectively.
WindowLeft must be less than BufferWidth - WindowWidth and WindowTop must be less than BufferHeight - WindowHeight.
WindowLeft and WindowTop are relative to the buffer.
To move the actual console window, this article has a good example.
I have used some of your code and code from the CodeProject sample. You can set window location and size both in a single function. No need to set Console.WindowHeight and Console.WindowWidth again. This is how my class looks:
class Program
{
const int SWP_NOZORDER = 0x4;
const int SWP_NOACTIVATE = 0x10;
[DllImport("kernel32")]
static extern IntPtr GetConsoleWindow();
[DllImport("user32")]
static extern bool SetWindowPos(IntPtr hWnd, IntPtr hWndInsertAfter,
int x, int y, int cx, int cy, int flags);
static void Main(string[] args)
{
Console.WindowWidth = 50;
Console.WindowHeight = 3;
Console.BufferWidth = 50;
Console.BufferHeight = 3;
Console.BackgroundColor = ConsoleColor.Black;
Console.ForegroundColor = ConsoleColor.DarkMagenta;
var screen = System.Windows.Forms.Screen.PrimaryScreen.Bounds;
var width = screen.Width;
var height = screen.Height;
SetWindowPosition(100, height - 300, 500, 100);
Console.Title = "My Title";
Console.WriteLine("");
Console.Write(" Press any key to close this window ...");
Console.ReadKey();
}
/// <summary>
/// Sets the console window location and size in pixels
/// </summary>
public static void SetWindowPosition(int x, int y, int width, int height)
{
SetWindowPos(Handle, IntPtr.Zero, x, y, width, height, SWP_NOZORDER | SWP_NOACTIVATE);
}
public static IntPtr Handle
{
get
{
//Initialize();
return GetConsoleWindow();
}
}
}

Run any console application
Click RMB on headline.
Choose properties option.
choose Position tab.
Uncheck box "Automatic choice"
Set console position as you want.

How do I set the focus to the Desktop from within my C# application

Winforms App. .Net 3.5.
I need to set the focus from my C# application to the user's desktop (almost like simulating a mouse click on the desktop).
Can someone please show me how to do this with C#? I just want to set focus on the desktop so the focus is no longer on my application but I want to do this from within my application.
Edit: An answer below works by setting the focus to the desktop, but it minimizes all the open windows on the user's desktop.
Is there a way I can maybe set the focus to the next open window on the desktop instead? I just want to get the focus off of my application (without minimizing my application or hiding it). I just want to move focus to somewhere else. Maybe the desktop was not the best choice if it will minimize all the user's open windows/applications.

This should do it for you.
using System;
using System.Runtime.InteropServices;
namespace ConsoleApplication1 {
class Program {
[DllImport("user32.dll", EntryPoint = "FindWindow", SetLastError = true)]
static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
[DllImport("user32.dll", EntryPoint = "SendMessage", SetLastError = true)]
static extern IntPtr SendMessage(IntPtr hWnd, Int32 Msg, IntPtr wParam, IntPtr lParam);
const int WM_COMMAND = 0x111;
const int MIN_ALL = 419;
const int MIN_ALL_UNDO = 416;
static void Main(string[] args) {
IntPtr lHwnd = FindWindow("Shell_TrayWnd", null);
SendMessage(lHwnd, WM_COMMAND, (IntPtr)MIN_ALL, IntPtr.Zero);
System.Threading.Thread.Sleep(2000);
SendMessage(lHwnd, WM_COMMAND, (IntPtr)MIN_ALL_UNDO, IntPtr.Zero);
}
}
}
Get Next Window
I don't have a code example ready for these two but I'm going to give you the links to both. The first think you need to do is call GetWindow. After doing that you'll want to call SwitchToThisWindow passing in the pointer you received from GetWindow.

You can add this COM object in your project:
Microsoft Shell Controls And Automation
And then just call:
Shell32.ShellClass shell = new Shell32.ShellClass();
shell.MinimizeAll();
This will minimize all the windows and then focus the desktop. Otherwise, if you have your window non-full screen then you can simulate the mouse click using:
//This is a replacement for Cursor.Position in WinForms
[System.Runtime.InteropServices.DllImport("user32.dll")]
static extern bool SetCursorPos(int x, int y);
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern void mouse_event(int dwFlags, int dx, int dy, int cButtons, int dwExtraInfo);
public const int MOUSEEVENTF_LEFTDOWN = 0x02;
public const int MOUSEEVENTF_LEFTUP = 0x04;
//This simulates a left mouse click
public static void LeftMouseClick(int xpos, int ypos)
{
SetCursorPos(xpos, ypos);
mouse_event(MOUSEEVENTF_LEFTDOWN, xpos, ypos, 0, 0);
mouse_event(MOUSEEVENTF_LEFTUP, xpos, ypos, 0, 0);
}
You can calculate coordinates by looking at your window startup location plus height/width and select a available space (that will be the desktop indeed).

Capture screenshot Including Semitransparent windows in .NET

I would like a relatively hack-free way to do this, any ideas? For example, the following takes a screenshot that doesn't include the semi-transparent window:
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Shown
Text = "Opaque Window"
Dim win2 As New Form
win2.Opacity = 0.5
win2.Text = "Tranparent Window"
win2.Show()
win2.Top = Top + 50
win2.Left = Left() + 50
Dim bounds As Rectangle = System.Windows.Forms.Screen.GetBounds(Point.Empty)
Using bmp As Bitmap = New Bitmap(bounds.Width, bounds.Height)
Using g As Graphics = Graphics.FromImage(bmp)
g.CopyFromScreen(Point.Empty, Point.Empty, bounds.Size)
End Using
bmp.Save("c:\temp\scn.gif")
End Using
Process.Start(New Diagnostics.ProcessStartInfo("c:\temp\scn.gif") With {.UseShellExecute = True})
End Sub
End Class
Either my google-fu really sucks or this is not as easy as it sounds. I'm pretty sure why this is happening because of the way the video driver would have to separate the memory to make this work, but I don't care why it doesn't work, I just want to do it without...
* print-screen key hacks
* 3rd party software
* SDK functions are OK but I'll upvote every object owned by the user that can show me it in pure framework (Just kidding but it would be nice).
If This is the only way to do it, how to I do that in VB?
1M thanks.

Forms that have the TransparencyKey or Opacity property set are so-called layered windows. They are shown using the "overlay" feature of the video adapter. Which make them being able to have their transparency effects.
Capturing them requires turning on the CopyPixelOperation.CaptureBlt option in the CopyFromScreen overload that accepts the CopyPixelOperation argument.
Unfortunately, this overload has a critical bug that prevents this from working. It doesn't validate the value properly. Still not fixed in .NET 4.0. There is no other good fix but fall back to using P/Invoke to make the screen shot. Here's an example:
using System;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace WindowsApplication1 {
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e) {
Size sz = Screen.PrimaryScreen.Bounds.Size;
IntPtr hDesk = GetDesktopWindow();
IntPtr hSrce = GetWindowDC(hDesk);
IntPtr hDest = CreateCompatibleDC(hSrce);
IntPtr hBmp = CreateCompatibleBitmap(hSrce, sz.Width, sz.Height);
IntPtr hOldBmp = SelectObject(hDest, hBmp);
bool b = BitBlt(hDest, 0, 0, sz.Width, sz.Height, hSrce, 0, 0, CopyPixelOperation.SourceCopy | CopyPixelOperation.CaptureBlt);
Bitmap bmp = Bitmap.FromHbitmap(hBmp);
SelectObject(hDest, hOldBmp);
DeleteObject(hBmp);
DeleteDC(hDest);
ReleaseDC(hDesk, hSrce);
bmp.Save(#"c:\temp\test.png");
bmp.Dispose();
}
// P/Invoke declarations
[DllImport("gdi32.dll")]
static extern bool BitBlt(IntPtr hdcDest, int xDest, int yDest, int
wDest, int hDest, IntPtr hdcSource, int xSrc, int ySrc, CopyPixelOperation rop);
[DllImport("user32.dll")]
static extern bool ReleaseDC(IntPtr hWnd, IntPtr hDc);
[DllImport("gdi32.dll")]
static extern IntPtr DeleteDC(IntPtr hDc);
[DllImport("gdi32.dll")]
static extern IntPtr DeleteObject(IntPtr hDc);
[DllImport("gdi32.dll")]
static extern IntPtr CreateCompatibleBitmap(IntPtr hdc, int nWidth, int nHeight);
[DllImport("gdi32.dll")]
static extern IntPtr CreateCompatibleDC(IntPtr hdc);
[DllImport("gdi32.dll")]
static extern IntPtr SelectObject(IntPtr hdc, IntPtr bmp);
[DllImport("user32.dll")]
public static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll")]
public static extern IntPtr GetWindowDC(IntPtr ptr);
}
}
Fwiw, a later Windows version provided a workaround for this bug. Not exactly sure which, I think it was Win7 SP1. The BitBlt() function will now do what you want if you pass only the CopyPixelOperation.CaptureBlt option. But of course that workaround wasn't applied retro-actively to earlier Windows versions so you can't really depend on it.