C#

public class ByteMatrix
{
    byte[,] _matrix;
    int _n;
    int _m;
    public ByteMatrix(int n, int m)
    {
        _matrix = new byte[n, m];
        _n = n;
        _m = m;
    }
    // Methods, indexers and properties to add, remove, etc, as needed
    // Import the unmanaged function here, as private
    [DllImport ... whatever]
    private static extern int unmanagedFunction(IntPtr array, int n, int m);
    // Wrap the unmanaged function whithin this class
    public int CallUnmanaged() // Here a good name, of course
    {
        // Pin the _matrix in managed heap first
        GCHandle handle = GCHandle.Alloc(_matrix, GCHandleType.Pinned);
        int ret = unmanagedFunction(handle.AddrOfPinnedObject(), _n, _m);
        // Release the handle
        handle.Free();

        return ret;
    }

int CallUnmanagedMethod(List<byte[]> lst)
{
    GCHandle[] handleArray = new GCHandle[lst.Count];

    for (int i=0; i<lst.Count; i++)
        handleArray[i] = GCHandle.Alloc(lst[i], GCHandleType.Pinned);

    IntPtr[] pointers = (from GCHandle handle in handleArray select
                            handle.GetAddrOfPinnedObject()).ToArray();

    // Call the unmananged method here
    int ret = unmanagedMethod(pointers, ... // rest of the parameters

    // Release the handles
    foreach (GCHandle handle in handleArray)
        handle.Free();

    return ret;
}

_Erik_ wrote:

I don't have time to make tests, but I am trying to help you. However, I won't be able to do so if you discard my suggestions before giving them a try. I

GCHandle handle2 = handle1;

try { foo; } catch {}

eg_Anubhava wrote:

As you know In vb.net or vb6 the On Error Resume Next is use to error handling

string[] veryValuableDataFromUsers = new string[10];
veryValuableDataFromUsers [10] = myUserTextBox.Text;
foreach (string data in veryValuableDataFromUsers)
   {
   SaveMyData(data);
   }

eg_Anubhava wrote:

As you know In vb.net or vb6 the On Error Resume Next is use to error handling

On Error Resume Next
Foo()

try
{
    Foo();
}
catch
{
    //ignore exceptions
}