有没有一种方法可以将在流或者数组上收集的数据映射到数据结构，反之亦然？
在C ++中，这仅是将指向流的指针转换为我要使用的数据类型的问题(反之亦然)
例如：在C ++中

Mystruct * pMyStrct = (Mystruct*)&SomeDataStream;
pMyStrct->Item1 = 25;

int iReadData = pMyStrct->Item2;

显然，除非我们在读取传入数据时确定流数据的质量，否则C ++方法是非常不安全的，但是对于传出数据而言，这是非常快速和容易的。

解决方案

回答

如果双方的.net：

认为我们应该使用二进制序列化并发送byte []结果。

信任结构完全可破解可能会很麻烦。

我们将需要支付一些开销(cpu和网络)，但是这样做是安全的。

回答

如果我们需要手动填充每个成员变量，则可以使用FormatterServices按顺序检索与对象关联的变量类型的列表，就其涉及的原语进行概括。我必须在一个项目中执行此操作，在该项目中，我会遇到很多不同的消息类型，并且我绝对不想为每条消息编写序列化器/反序列化器。

这是我用来从byte []进行反序列化的代码。

public virtual bool SetMessageBytes(byte[] message)
    {
        MemberInfo[] members = FormatterServices.GetSerializableMembers(this.GetType());
        object[] values = FormatterServices.GetObjectData(this, members);
        int j = 0;

        for (int i = 0; i < members.Length; i++)
        {
            string[] var = members[i].ToString().Split(new char[] { ' ' });
            switch (var[0])
            {
                case "UInt32":
                    values[i] = (UInt32)((message[j] << 24) + (message[j + 1] << 16) + (message[j + 2] << 8) + message[j + 3]);
                    j += 4;
                    break;
                case "UInt16":
                    values[i] = (UInt16)((message[j] << 8) + message[j + 1]);
                    j += 2;
                    break;
                case "Byte":
                    values[i] = (byte)message[j++];
                    break;
                case "UInt32[]":
                    if (values[i] != null)
                    {
                        int len = ((UInt32[])values[i]).Length;
                        byte[] b = new byte[len * 4];
                        Array.Copy(message, j, b, 0, len * 4);
                        Array.Copy(Utilities.ByteArrayToUInt32Array(b), (UInt32[])values[i], len);
                        j += len * 4;
                    }
                    break;
                case "Byte[]":
                    if (values[i] != null)
                    {
                        int len = ((byte[])values[i]).Length;
                        Array.Copy(message, j, (byte[])(values[i]), 0, len);
                        j += len;
                    }
                    break;
                default:
                    throw new Exception("ByteExtractable::SetMessageBytes Unsupported Type: " + var[1] + " is of type " +  var[0]);
            }
        }
        FormatterServices.PopulateObjectMembers(this, members, values);
        return true;
    }

回答

大多数人使用.NET序列化(有更快的二进制文件和更慢的XML格式化程序，它们都依赖于反射并且在一定程度上可以容忍版本)

但是，如果我们想要最快(不安全)的方式，为什么不这样做：

写作：

YourStruct o = new YourStruct();
byte[] buffer = new byte[Marshal.SizeOf(typeof(YourStruct))];
GCHandle handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
Marshal.StructureToPtr(o, handle.AddrOfPinnedObject(), false);
handle.Free();

读：

handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
o = (YourStruct)Marshal.PtrToStructure(handle.AddrOfPinnedObject(), typeof(YourStruct));
handle.Free();

回答

如果lubos hasko的回答还不够安全，还有一种真正不安全的方法，即使用
C＃中的指针。这是我遇到的一些提示和陷阱：

using System;
using System.Runtime.InteropServices;
using System.IO;
using System.Diagnostics;

// Use LayoutKind.Sequential to prevent the CLR from reordering your fields.
[StructLayout(LayoutKind.Sequential)]
unsafe struct MeshDesc
{
    public byte NameLen;
    // Here fixed means store the array by value, like in C,
    // though C# exposes access to Name as a char*.
    // fixed also requires 'unsafe' on the struct definition.
    public fixed char Name[16];
    // You can include other structs like in C as well.
    public Matrix Transform;
    public uint VertexCount;
    // But not both, you can't store an array of structs.
    //public fixed Vector Vertices[512];
}

[StructLayout(LayoutKind.Sequential)]
unsafe struct Matrix
{
    public fixed float M[16];
}

// This is how you do unions
[StructLayout(LayoutKind.Explicit)]
unsafe struct Vector
{
    [FieldOffset(0)]
    public fixed float Items[16];
    [FieldOffset(0)]
    public float X;
    [FieldOffset(4)]
    public float Y;
    [FieldOffset(8)]
    public float Z;
}

class Program
{
    unsafe static void Main(string[] args)
    {
        var mesh = new MeshDesc();
        var buffer = new byte[Marshal.SizeOf(mesh)];

        // Set where NameLen will be read from.
        buffer[0] = 12;
        // Use Buffer.BlockCopy to raw copy data across arrays of primitives.
        // Note we copy to offset 2 here: char's have alignment of 2, so there is
        // a padding byte after NameLen: just like in C.
        Buffer.BlockCopy("Hello!".ToCharArray(), 0, buffer, 2, 12);

        // Copy data to struct
        Read(buffer, out mesh);

        // Print the Name we wrote above:
        var name = new char[mesh.NameLen];
        // Use Marsal.Copy to copy between arrays and pointers to arrays.
        unsafe { Marshal.Copy((IntPtr)mesh.Name, name, 0, mesh.NameLen); }
        // Note you can also use the String.String(char*) overloads
        Console.WriteLine("Name: " + new string(name));

        // If Erik Myers likes it...
        mesh.VertexCount = 4711;

        // Copy data from struct:
        // MeshDesc is a struct, and is on the stack, so it's
        // memory is effectively pinned by the stack pointer.
        // This means '&' is sufficient to get a pointer.
        Write(&mesh, buffer);

        // Watch for alignment again, and note you have endianess to worry about...
        int vc = buffer[100] | (buffer[101] << 8) | (buffer[102] << 16) | (buffer[103] << 24);
        Console.WriteLine("VertexCount = " + vc);
    }

    unsafe static void Write(MeshDesc* pMesh, byte[] buffer)
    {
        // But byte[] is on the heap, and therefore needs
        // to be flagged as pinned so the GC won't try to move it
        // from under you - this can be done most efficiently with
        // 'fixed', but can also be done with GCHandleType.Pinned.
        fixed (byte* pBuffer = buffer)
            *(MeshDesc*)pBuffer = *pMesh;
    }

    unsafe static void Read(byte[] buffer, out MeshDesc mesh)
    {
        fixed (byte* pBuffer = buffer)
            mesh = *(MeshDesc*)pBuffer;
    }
}