Return C++ array to C#

I have implemented the solution Sriram has proposed. In case someone wants it here it is.

In C++ you create a DLL with this code:

extern "C" __declspec(dllexport) int* test() {    int len = 5;    int * arr=new int[len+1];    arr[0]=len;    arr[1]=1;    arr[2]=2;    arr[3]=3;    arr[4]=4;    arr[5]=5;        return arr;}extern "C" __declspec(dllexport) int ReleaseMemory(int* pArray){    delete[] pArray;    return 0;}

The DLL will be called InteropTestApp.

Then you create a console application in C#.

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Runtime.InteropServices;namespace DLLCall{    class Program    {        [DllImport("C:\\Devs\\C++\\Projects\\Interop\\InteropTestApp\\Debug\\InteropTestApp.dll")]        public static extern IntPtr test();        [DllImport("C:\\Devs\\C++\\Projects\\Interop\\InteropTestApp\\Debug\\InteropTestApp.dll", CallingConvention = CallingConvention.Cdecl)]        public static extern int ReleaseMemory(IntPtr ptr);        static void Main(string[] args)        {            IntPtr ptr = test();            int arrayLength = Marshal.ReadInt32(ptr);            // points to arr[1], which is first value            IntPtr start = IntPtr.Add(ptr, 4);            int[] result = new int[arrayLength];            Marshal.Copy(start, result, 0, arrayLength);            ReleaseMemory(ptr);            Console.ReadKey();        }    }}

result now contains the values 1,2,3,4,5.

Hope that helps.