struct rankPoint{

    float sim;

};

extern "C" __declspec(dllexport) int getRank(rankPoint prank[]){

    for(int i = ; i < ; i++)

    prank[i].sim = ;

    for(int i = ; i < ; i++)

    prank[i].sim = i;

    return ;

}

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Runtime.InteropServices;

namespace DllTest

{

    [StructLayout(LayoutKind.Sequential)]

    struct rankP

    {

        public float mark;

    }

    public class Cpp {

        [DllImport("Cdll.dll")]

        public static extern int getRank(IntPtr p);

    }

    public partial class _Default : System.Web.UI.Page

    {

        protected void Page_Load(object sender, EventArgs e)

        {

            int size = Marshal.SizeOf(typeof(rankP)) * ;

            byte[] bytes = new byte[size];

            IntPtr pBuff = Marshal.AllocHGlobal(size);

            rankP[] rBuf = new rankP[];

            Cpp.getRank(pBuff);

            for(int i = ; i < ; i++)

            {

                IntPtr pPointor = new IntPtr(pBuff.ToInt64() + Marshal.SizeOf(typeof(rankP)) * i);

                rBuf[i] = (rankP)Marshal.PtrToStructure(pPointor,typeof(rankP));

            }

            int si = ;  //设置断点监测，的确修改了rBuf数组，也就是实现了数组的传递，只不过是通过结构体实现的

            Marshal.FreeHGlobal(pBuff);

        }

    }

}