c# - WPF CreateBitmapSourceFromHBitmap() 内存泄漏

Question

我需要逐像素绘制图像并将其显示在 WPF 中。我试图通过使用 System.Drawing.Bitmap 然后使用 CreateBitmapSourceFromHBitmap() 为 WPF Image 控件创建 BitmapSource 来执行此操作。我在某处发生内存泄漏，因为当重复调用 CreateBitmapSourceFromBitmap() 时，内存使用量会上升，并且在应用程序结束之前不会下降。如果我不调用 CreateBitmapSourceFromBitmap()，内存使用量不会有明显变化。

for (int i = 0; i < 100; i++)
{
    var bmp = new System.Drawing.Bitmap(1000, 1000);
    var source = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(
        bmp.GetHbitmap(), IntPtr.Zero, Int32Rect.Empty,
        System.Windows.Media.Imaging.BitmapSizeOptions.FromEmptyOptions());
    source = null;
    bmp.Dispose();
    bmp = null;
}

如何释放 BitmapSource 内存？

Answer 1

MSDN for Bitmap.GetHbitmap()状态:

Remarks

You are responsible for calling the GDI DeleteObject method to free the memory used by the GDI bitmap object.

所以使用下面的代码:

// at class level
[System.Runtime.InteropServices.DllImport("gdi32.dll")]
public static extern bool DeleteObject(IntPtr hObject);

// your code
using (System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(1000, 1000)) 
{
    IntPtr hBitmap = bmp.GetHbitmap(); 

    try 
    {
        var source = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(hBitmap, IntPtr.Zero, Int32Rect.Empty, System.Windows.Media.Imaging.BitmapSizeOptions.FromEmptyOptions());
    }
    finally 
    {
        DeleteObject(hBitmap);
    }
}

我还用 using 语句替换了您的 Dispose() 调用。