C#不通过byte[]，直接对内存映射文件复制内存

背景

多个进程直接需要传递大量图片，所以对性能要求较高。支付复制内存显然比转成byte[]再复制优越。

命名空间

using System;

using System.Diagnostics;

using System.Runtime.InteropServices;

代码

public CMainTestForm()

{

InitializeComponent();

WriteIntToMemFile(34);

}

static unsafe void WriteIntToMemFile(int i)

{

using (var mmf = System.IO.MemoryMappedFiles.MemoryMappedFile.CreateNew("HZD20230925", 42))

using (var view = mmf.CreateViewAccessor())

{

byte* poke = null;

view.SafeMemoryMappedViewHandle.AcquirePointer(ref poke);

CopyMemory(new System.IntPtr(poke), new System.IntPtr(&i), sizeof(int));

view.SafeMemoryMappedViewHandle.AcquirePointer(ref poke);

int iRead = view.ReadInt32(0);

Debug.Assert(iRead == i);

}

}

DllImport("kernel32.dll", EntryPoint = "RtlMoveMemory", CharSet = CharSet.Ansi)

public extern static long CopyMemory(IntPtr dest, IntPtr source, int size);

测试环境

Win7 VS2022