How to use SampleGrad in Unity shader

The code in hlsl but I can’t use it.

Unity says “sampler2D object does not have methods”

There’s the detail SampleGrad (DirectX HLSL Texture Object)

The article relate to A Closer Look At Parallax Occlusion Mapping

Hi, I am working on the same problem. I have found this post which is published in 2016.Here is the link: