PrintWindow api with possible solution for capture screenshot Google Chrome window

Question

Hi,
as all you know, PrintWindow api give us a black image when us want a capture screenshot  of Google Chrome window. So, a friend said me that a possible solution for this problem is: 
Reduce Google Chrome window for -1px in both sides and after this, reset  to original size. And so, will repaint again.
Based on code below, someone could help me make this? sincerely I don't know where begin.
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr FindWindow(string lpClassName, string lpWindowName);
[DllImport("user32.dll", SetLastError = true)]
static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow);
[DllImport("user32.dll")]
private static extern IntPtr GetDC(IntPtr WindowHandle);
[DllImport("user32.dll")]
private static extern void ReleaseDC(IntPtr WindowHandle, IntPtr DC);
[DllImport("user32.dll")]
private static extern IntPtr GetWindowRect(IntPtr WindowHandle, ref Rect rect);
[DllImport("User32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool PrintWindow(IntPtr hwnd, IntPtr hDC, uint nFlags);
[StructLayout(LayoutKind.Sequential)]
private struct Rect
public int Left;
public int Top;
public int Right;
public int Bottom;
public static Bitmap Capture(IntPtr handle)
Rect rect = new Rect();
GetWindowRect(handle, ref rect);
Bitmap Bmp = new Bitmap(rect.Right - rect.Left, rect.Bottom - rect.Top);
Graphics memoryGraphics = Graphics.FromImage(Bmp);
IntPtr dc = memoryGraphics.GetHdc();
bool success = PrintWindow(handle, dc, 0);
memoryGraphics.ReleaseHdc(dc);
return Bmp;
private void button1_Click(object sender, EventArgs e)
IntPtr WindowHandle = FindWindowEx(IntPtr.Zero, IntPtr.Zero, "Chrome_WidgetWin_1", null);
Bitmap BMP = Capture(WindowHandle);
BMP.Save("C:\\Foo.bmp");
BMP.Dispose();
Any suggestions here is appreciated.

Answer 1

Hello,
I would prefer capture the screen rather than get it from that application directly.
It has been discussed in the following thread.
Is there any way to hide Chrome window and capture a screenshot or convert the Chrome window to image?
In this case, you could remove the line "ShowWindowAsync(mainHandle, 0); " since you don't want to hide it.
using System;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Drawing.Imaging;
[DllImport("user32.dll")]
private static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);
[DllImport("user32.dll")]
public static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);
[DllImport("user32.dll")]
public static extern bool PrintWindow(IntPtr hWnd, IntPtr hdcBlt, int nFlags);
public WhateverMethod()
//initialize process and get hWnd
Process chrome = Process.Start("chrome.exe","http://www.cnn.com");
//wait for chrome window to open AND page to load (important for process refresh)
//you might need to increase the sleep time for the page to load or monitor the "loading" title on Chrome
System.Threading.Thread.Sleep(4000);
chrome.Refresh();
IntPtr mainHandle = chrome.MainWindowHandle;
RECT rc;
GetWindowRect(mainHandle, out rc);
Bitmap bmp = new Bitmap(rc.Width, rc.Height, PixelFormat.Format32bppArgb);
Graphics gfxBmp = Graphics.FromImage(bmp);
IntPtr hdcBitmap = gfxBmp.GetHdc();
PrintWindow(mainHandle, hdcBitmap, 0);
gfxBmp.ReleaseHdc(hdcBitmap);
gfxBmp.Dispose();
bmp.Save("c:\\temp\\test.png", ImageFormat.Png);
ShowWindowAsync(mainHandle, 0);
[StructLayout(LayoutKind.Sequential)]
public struct RECT
private int _Left;
private int _Top;
private int _Right;
private int _Bottom;
public RECT(RECT Rectangle)
: this(Rectangle.Left, Rectangle.Top, Rectangle.Right, Rectangle.Bottom)
public RECT(int Left, int Top, int Right, int Bottom)
_Left = Left;
_Top = Top;
_Right = Right;
_Bottom = Bottom;
public int X
get { return _Left; }
set { _Left = value; }
public int Y
get { return _Top; }
set { _Top = value; }
public int Left
get { return _Left; }
set { _Left = value; }
public int Top
get { return _Top; }
set { _Top = value; }
public int Right
get { return _Right; }
set { _Right = value; }
public int Bottom
get { return _Bottom; }
set { _Bottom = value; }
public int Height
get { return _Bottom - _Top; }
set { _Bottom = value + _Top; }
public int Width
get { return _Right - _Left; }
set { _Right = value + _Left; }
public Point Location
get { return new Point(Left, Top); }
set
_Left = value.X;
_Top = value.Y;
public Size Size
get { return new Size(Width, Height); }
set
_Right = value.Width + _Left;
_Bottom = value.Height + _Top;
public static implicit operator Rectangle(RECT Rectangle)
return new Rectangle(Rectangle.Left, Rectangle.Top, Rectangle.Width, Rectangle.Height);
public static implicit operator RECT(Rectangle Rectangle)
return new RECT(Rectangle.Left, Rectangle.Top, Rectangle.Right, Rectangle.Bottom);
public static bool operator ==(RECT Rectangle1, RECT Rectangle2)
return Rectangle1.Equals(Rectangle2);
public static bool operator !=(RECT Rectangle1, RECT Rectangle2)
return !Rectangle1.Equals(Rectangle2);
public override string ToString()
return "{ + _Left + "; " + " + _Top + "; Right: " + _Right + "; Bottom: " + _Bottom + "}";
public override int GetHashCode()
return ToString().GetHashCode();
public bool Equals(RECT Rectangle)
return Rectangle.Left == _Left && Rectangle.Top == _Top && Rectangle.Right == _Right && Rectangle.Bottom == _Bottom;
public override bool Equals(object Object)
if (Object is RECT)
return Equals((RECT)Object);
else if (Object is Rectangle)
return Equals(new RECT((Rectangle)Object));
return false;
And the key method used is the one shared in
Get a screenshot of a specific application.
Regards,
Carl
We are trying to better understand customer views on social support experience, so your participation in this interview project would be greatly appreciated if you have time. Thanks for helping make community forums a great place.
Click
HERE to participate the survey.