Unity 5 checking if player isGrounded

I having trouble trying to figure out how to check the player object isGrounded. I was following a tutorial on Youtube and I recieve a error message saying that the code I used is obsolete. I have tried to look for a solution for it on the Unity community but only found out of date forum pages or irrelevant answers to my question. Thank you!

I figured out the issue.

disToGround = GetComponent.().bounds.extents.y;

return Physics.Raycast(transform.position, -Vector3.up, disToGround + 0.1);