Question

我想从另一个窗口获取像素颜色。我的代码是：

  using System;
  using System.Drawing;
  using System.Runtime.InteropServices;


 sealed class Win32
  {
      [DllImport("user32.dll")]
      static extern IntPtr GetDC(IntPtr hwnd);

      [DllImport("user32.dll")]
      static extern Int32 ReleaseDC(IntPtr hwnd, IntPtr hdc);

      [DllImport("gdi32.dll")]
      static extern uint GetPixel(IntPtr hdc, int nXPos, int nYPos);

      static public System.Drawing.Color GetPixelColor(int x, int y)
      {
       IntPtr hdc = GetDC(IntPtr.Zero);
       uint pixel = GetPixel(hdc, x, y);
       ReleaseDC(IntPtr.Zero, hdc);
       Color color = Color.FromArgb((int)(pixel & 0x000000FF),
                    (int)(pixel & 0x0000FF00) >> 8,
                    (int)(pixel & 0x00FF0000) >> 16);
       return color;
      }
   }

问题是这段代码正在扫描整个屏幕，这不是我想要的。想法是修改代码以基于另一个应用程序屏幕边界扫描像素颜色。也许是FindWindow或GetWindow的东西？提前谢谢。

Answer 1

您可以按照标题导入FindWindow来查找窗口：

[DllImport("user32.dll", EntryPoint = "FindWindow", SetLastError = true)]
static extern IntPtr FindWindowByCaption(IntPtr ZeroOnly, string lpWindowName);

static IntPtr FindWindowByCaption(string caption)
{
    return FindWindowByCaption(IntPtr.Zero, caption);
}

然后，使用处理程序为您的GetPixelColor添加一个额外的参数：

static public System.Drawing.Color GetPixelColor(IntPtr hwnd, int x, int y)
{
    IntPtr hdc = GetDC(hwnd);
    uint pixel = GetPixel(hdc, x, y);
    ReleaseDC(hwnd, hdc);
    Color color = Color.FromArgb((int)(pixel & 0x000000FF),
                    (int)(pixel & 0x0000FF00) >> 8,
                    (int)(pixel & 0x00FF0000) >> 16);
    return color;
}

用法：

var title = "windows caption";

var hwnd = FindWindowByCaption(title);

var pixel = Win32.GetPixelColor(hwnd, x, y);

C＃从另一个窗口获取像素颜色

1 个答案: