Using HLSL TextureArrays in Custom Node

Hi there, people!
I have the question. How i can use HLSL texture arrays in custom material node? Declaring, initializing and sampling?
For example, i have several custom node inputs:

  • texA (Texture Object)
  • texB (Texture Object)
  • texC (Texture Object)
  • index (float)

So, how i can put these thee tex into an texture array tex[] and then make sampling form tex[index]?
Please, give me this several code lines.
Thanks )