views:

208

answers:

2

Greetings.

In C#: If I have an int[] array declared like this

int[] array = new array[size];

there is an way to get the IntPtr from this array?

The thing is that I'm using the EmguCV framework, and there is an constructor to create an image which takes an IntPtr to the pixel data, in order to build an image from an array (int[]).

Image<Gray,Int32> result = new Image<Gray,int>(bitmap.Width,bitmap.Height,stride,"**array.toPointer??**");

By the way if someone could told me how to calculate the stride, that would be great.

+1  A: 

Use unsafe code, like this:

unsafe
{
  fixed (int* pArray = array)
  {
    IntPtr intPtr = new IntPtr((void *) pArray);
  }
}
Marcel Gheorghita
And of course note that intPtr only points to the array *while control is in the fixed block*. Once you leave the fixed block the garbage collector is free to move pArray around in memory again and the intPtr could therefore be pointing to garbage.
Eric Lippert
+1  A: 

You should be able to do this without unsafe code using GCHandle. Here is a sample:

GCHandle handle = GCHandle.Alloc(array, GCHandleType.Pinned);
try
{
    IntPtr pointer = handle.AddrOfPinnedObject();
}
finally
{
    if (handle.IsAllocated)
    {
        handle.Free();
    }
}
Bryan