c# - 从 IntPtr 获取结构数组

Question

我有这样的结构

struct MyStruct
{
    public int field1;
    public int field2;
    public int field3;
}

我有指向这个结构数组的指针。所以，我需要从这个指针获取数组。我尝试使用 Marshal.PtrToStructure，但出现内存读取错误。这是我的方法:

public MyStruct[] GetArrayOfStruct(IntPtr pointerToStruct, int length)
{
    var sizeInBytes = Marshal.SizeOf(typeof(TCnt));
    MyStruct[] output = new MyStruct[length];

    for (int i = 0; i < length; i++)
    {
        IntPtr p = new IntPtr((pointerToStruct.ToInt32() + i * sizeInBytes));

        output[i] = (MyStruct)System.Runtime.InteropServices.Marshal.PtrToStructure(p, typeof(MyStruct));
    }

    return output;
}

那么，我做错了什么？

Answer 1

这个函数对我有用，假设结构的大小是固定的:

public static void MarshalUnmananagedArray2Struct<T>(IntPtr unmanagedArray, int length, out T[] mangagedArray)
{
    var size = Marshal.SizeOf(typeof(T));
    mangagedArray = new T[length];

    for (int i = 0; i < length; i++)
    {
        IntPtr ins = new IntPtr(unmanagedArray.ToInt64() + i * size);
        mangagedArray[i] = Marshal.PtrToStructure<T>(ins);
    }
 }