c# - Windows 10 上的 .NET FontFamily 内存泄漏

Question

在 Windows 10 上，System.Drawing.FontFamily.IsStyleAvailable 方法似乎将分配的空间留在内存中，即使在调用 Dispose 方法之后也是如此。

我写了一个简单的控制台应用程序来测试它:

using System;
using System.Drawing;
using System.Diagnostics;

namespace ConsoleApplication1
{
    class Program
    {
        static string getMemoryStatusString()
        {
            using (Process p = Process.GetCurrentProcess())
            {
                return "(p: " + p.PrivateMemorySize64 + ", v:" + p.VirtualMemorySize64 + ")";
            }
        }

        static void Main(string[] args)
        {
            string s = getMemoryStatusString();
            foreach(FontFamily fontFamily in FontFamily.Families)
            {
                Console.Write(fontFamily.Name + " " + getMemoryStatusString() + " -> ");

                fontFamily.IsStyleAvailable(FontStyle.Regular);
                fontFamily.Dispose();

                Console.WriteLine(getMemoryStatusString());
            }
            string e = getMemoryStatusString();
            Console.WriteLine(s + " -> " + e);
            Console.ReadLine();
        }
    }
}

知道为什么会这样吗？

提前致谢!

Answer 1

如果存在内存泄漏，它将在 gdiplus.dll 中, FontFamily.IsStyleAvailable()实际上对 GdipIsStyleAvailable() 进行了外部调用.

来自 ILSpy:

public bool IsStyleAvailable(FontStyle style)
{
    int num2;
    int num = SafeNativeMethods.Gdip.GdipIsStyleAvailable(new HandleRef(this, this.NativeFamily), style, out num2);
    if (num != 0)
    {
        throw SafeNativeMethods.Gdip.StatusException(num);
    }
    return num2 != 0;
}

依次定义为:

[DllImport("gdiplus.dll", CharSet = CharSet.Unicode, ExactSpelling = true, SetLastError = true)]
internal static extern int GdipIsStyleAvailable(HandleRef family, FontStyle style, out int isStyleAvailable);