DeleteObject在哪里

抱歉，我在前面的代码中漏写了DeleteObject函数的定义，这里给出完整的代码，包括DeleteObject函数的定义：

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

public class WindowCapture
{
    [DllImport("User32.dll")]
    public static extern IntPtr GetDC(IntPtr hwnd);

    [DllImport("User32.dll")]
    public static extern void ReleaseDC(IntPtr hwnd, IntPtr dc);

    [DllImport("gdi32.dll")]
    public static extern IntPtr CreateCompatibleBitmap(IntPtr dc, int width, int height);

    [DllImport("gdi32.dll")]
    public static extern IntPtr CreateCompatibleDC(IntPtr dc);

    [DllImport("gdi32.dll")]
    public static extern IntPtr SelectObject(IntPtr dc, IntPtr obj);

    [DllImport("gdi32.dll")]
    public static extern bool BitBlt(IntPtr dcDest, int xDest, int yDest, int wDest, int hDest, IntPtr dcSrc, int xSrc, int ySrc, int rasterOp);

    [DllImport("gdi32.dll")]
    public static extern bool DeleteObject(IntPtr obj);

    public static Bitmap CaptureWindow(IntPtr hwnd)
    {
        // 获取窗口的设备上下文
        IntPtr hdcSrc = GetDC(hwnd);
        if (hdcSrc == IntPtr.Zero)
        {
            return null;
        }

        // 创建一个兼容的设备上下文和位图
        IntPtr hdcDest = CreateCompatibleDC(hdcSrc);
        IntPtr hbmDest = CreateCompatibleBitmap(hdcSrc, 100, 100);
        if (hdcDest == IntPtr.Zero || hbmDest == IntPtr.Zero)
        {
            ReleaseDC(hwnd, hdcSrc);
            return null;
        }

        // 将位图选入设备上下文
        IntPtr hbmOld = SelectObject(hdcDest, hbmDest);

        // 复制窗口的内容到位图中
        if (!BitBlt(hdcDest, 0, 0, 100, 100, hdcSrc, 0, 0, 0x00CC0020))
        {
            SelectObject(hdcDest, hbmOld);
            DeleteObject(hbmDest);
            DeleteDC(hdcDest);
            ReleaseDC(hwnd, hdcSrc);
            return null;
        }

        // 恢复设备上下文并释放资源
        SelectObject(hdcDest, hbmOld);
        DeleteObject(hbmDest);
        DeleteDC(hdcDest);
        ReleaseDC(hwnd, hdcSrc);

        // 返回位图
        return Bitmap.FromHbitmap(hbmDest);
    }
}

这里添加了DllImport语句，用于导入DeleteObject函数的定义。DeleteObject函数用于删除GDI对象，如位图对象、画笔对象、画刷对象等。在截取窗口截图时，需要在最后删除位图对象，以释放内存。