问题
I got a small problem which I can't seem to find the answer of. I have a application that gets certain processes and gets the window size of it. Only the problem is it takes a percentage of the actual screen size (which the user sees).
I want to make a screenshot of the application, but if I use the Rect of the window I get a smaller screen than it is, because the resolotion is 125%. This means my original resolution which gets outputted (1280 * 800) is smaller then my screen resolution (1600 * 1000) you can understand that this small hiccup makes my program unreliable. My question is how to fix this?
I've created a manifest which I set DPIAware to true. Also I disabled the Visual Studio hosting in the debug. But it doesn't help. I still get the same values and the same problem. Here is my code snippet for the actual screenshotting:
RECT Rect = new RECT();
System.Diagnostics.Process[] p = System.Diagnostics.Process.GetProcessesByName("Process");
ShowWindow(p[0].MainWindowHandle, 9);
SetForegroundWindow(p[0].MainWindowHandle);
if (GetWindowRect(p[0].MainWindowHandle, ref Rect))
{
var bmp = new Bitmap(Rect.Width, Rect.Height);
var graphics = Graphics.FromImage(bmp);
graphics.CopyFromScreen(Rect.Left, Rect.Top, 0, 0, new Size(Rect.Width, Rect.Height), CopyPixelOperation.SourceCopy);
bmp.Save(@"C:\Screenshots\temp1.png");
}
This gives me an screenshot of 1280 * 800, not enough to cover the whole process, which is 1600 * 1000. Everything is off because the screen coordinates are not right. If I multiply everything by 1,25 it will be alright but that is not a solution because I don't know what the DPI settings on other PC's are.
EDIT 3:
I'll post the full code with the RECT in it.
RECT Rect = new RECT();
System.Diagnostics.Process[] p = System.Diagnostics.Process.GetProcessesByName("LoLPatcherUx");
ShowWindow(p[0].MainWindowHandle, 9);
SetForegroundWindow(p[0].MainWindowHandle);
if (GetWindowRect(p[0].MainWindowHandle, ref Rect))
{
int processH = Rect.Bottom - Rect.Top;
int processW = Rect.Right - Rect.Left;
float processWidth;
float processHeight;
SizeF dpi = GetCurrentDpi();
// Calc the scale.
SizeF scale = new SizeF()
{
Width = dpi.Width / 96f,
Height = dpi.Height / 96f
};
// Scale the rectangle.
processWidth = Rect.Width * scale.Width;
processHeight = Rect.Height * scale.Height;
var bmp = new Bitmap(lolPatcherBreedte, lolPatcherHoogte);
Graphics graphics = Graphics.FromImage(bmp);
graphics.CopyFromScreen(Rect.Left, Rect.Top, 0, 0, new Size(processW, processH));
bmp.Save(@"C:\Screenshots\temp1.png");
}
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: " + _Left + "; " + "Top: " + _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;
}
}
回答1:
You can get the current DPI setting via the
- Graphics.DpiX and
- Graphics.DpiY
properties.
This way you should be able to calculate it correctly (it's how I do it in one of my projects).
Just get these by creating a dummy Form and a Graphics object from it (if your code is being executed outside of a Form's context):
public static SizeF GetCurrentDpi()
{
using (Form form = new Form())
using (Graphics g = form.CreateGraphics())
{
var result = new SizeF()
{
Width = g.DpiX,
Height = g.DpiY
};
return result;
}
}
Control.CreateGraphics Method
Usage:
if (GetWindowRect(p[0].MainWindowHandle, ref Rect))
{
var bmp = new Bitmap(Rect.Width, Rect.Height);
Graphics graphics = Graphics.FromImage(bmp);
// Use the helper function to get the current dpi.
SizeF dpi = GetCurrentDpi();
// Calc the scale.
SizeF scale = new SizeF()
{
Width = dpi.Width / 96f,
Height = dpi.Height / 96f
};
// Scale the rectangle.
Rect.Width *= scale.Width;
Rect.Height *= scale.Height;
graphics.CopyFromScreen(Rect.Left, Rect.Top, 0, 0, new Size(Rect.Width, Rect.Height), CopyPixelOperation.SourceCopy);
bmp.Save(@"C:\Screenshots\temp1.png");
}
Demo:
class Program
{
[DllImport("user32.dll", SetLastError = true)]
static extern bool GetWindowRect(IntPtr hwnd, ref RECT lpRect);
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool ShowWindow(IntPtr hWnd, ShowWindowCommands nCmdShow);
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SetForegroundWindow(IntPtr hWnd);
static void Main(string[] args)
{
RECT rect = new RECT();
Process[] processes = System.Diagnostics.Process.GetProcessesByName("iexplore");
Process iexplore = processes.First();
ShowWindow(iexplore.MainWindowHandle, ShowWindowCommands.Restore);
SetForegroundWindow(iexplore.MainWindowHandle);
var result = GetWindowRect(iexplore.MainWindowHandle, ref rect);
RectangleF rectF = new RectangleF()
{
Location = new PointF(rect.Left, rect.Top),
Size = new SizeF(rect.Right - rect.Left + 1, rect.Bottom - rect.Top + 1)
};
var bmp = new Bitmap((int)rectF.Width, (int)rectF.Height);
Graphics graphics = Graphics.FromImage(bmp);
graphics.CopyFromScreen((int)rectF.Left, (int)rectF.Top, 0, 0, new Size((int)rectF.Width, (int)rectF.Height), CopyPixelOperation.SourceCopy);
bmp.Save(@"C:\temp\screenshot1.jpg", ImageFormat.Jpeg);
}
}
enum ShowWindowCommands
{
Hide = 0,
Normal = 1,
ShowMinimized = 2,
Maximize = 3,
ShowMaximized = 3,
ShowNoActivate = 4,
Show = 5,
Minimize = 6,
ShowMinNoActive = 7,
ShowNA = 8,
Restore = 9,
ShowDefault = 10,
ForceMinimize = 11
}
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left;
public int Top;
public int Right;
public int Bottom;
}
来源：https://stackoverflow.com/questions/27661545/dpi-aware-and-rect