BCE0020 error with animation

I am trying to get a 2D sprite to look like it is walking through the animator controller using a speed parameter. I feel like I’m getting really close except this error “BCE0020: An instance of type ‘UnityEngine.Rigidbody2D’ is required to access non static member ‘velocity’.” popped up. Could anyone take a look at my script and help me out? I’m rather new to unity.

#pragma strict

public var maxJumps = 0; // maximum numer of jumps
private var numJumps = 0; //number of current jumps

public var moveSpeed = 0;

private var facingRight = true; //initally sprite faces to the right

private var isWalking : boolean;

public var jumpheight = 0;

var animator : Animator;


function Start() {

animator = GetComponent("Animator");

}
function Update () {


	var x;
	var y; 


if (Input.GetKeyDown("space") && CanJump()){
	x = GetComponent(Rigidbody2D).velocity.x;

	GetComponent(Rigidbody2D).velocity = new Vector2(0, jumpheight);

	numJumps ++;
}
if (Input.GetKey (KeyCode.A))
 {
 	
	y = GetComponent(Rigidbody2D).velocity.y;
	GetComponent(Rigidbody2D).velocity = new Vector2(-moveSpeed, y);
	animator.SetFloat("Speed", GetComponent(Rigidbody2D.velocity.x));

	if (facingRight) {
		Flip();
	
	}
	}
if (Input.GetKey (KeyCode.D)) {
	y = GetComponent(Rigidbody2D).velocity.y;
	GetComponent(Rigidbody2D).velocity = new Vector2(moveSpeed, y);

	animator.SetFloat("Speed", GetComponent(Rigidbody2D.velocity.x));


	if (!facingRight) {
		Flip();
	
	}

}
}




function OnCollisionEnter2D (coll : Collision2D)
{
	if (coll.gameObject.CompareTag("Ground")) {
		numJumps = 0;
	}
	}
	function CanJump() {
	return numJumps < maxJumps;
	}


	function Flip() {
		var flipScale : Vector3;
		var rigidbody : Rigidbody2D;

		rigidbody = GetComponent(Rigidbody2D);

		flipScale = rigidbody.transform.localScale;
		flipScale.x *= -1; //flip horizontally

		rigidbody.transform.localScale = flipScale;

		facingRight = !facingRight; // now facing opposite direction
	}

it says that     	animator.SetFloat("Speed", GetComponent(Rigidbody2D.velocity.x)); is tripping the error. please help!

right now in your script you are using

" GetComponent(Rigidbody2D)."

to get rigidbody from the game object

but after unity 5 this scripting is changed so you have to use

“gameobject.GetComponent.().”