bool parameter in Animator

trying to get a game object to expand through a user input- I have the animation in the Animator controller, and I have a bool named “expand” as a parameter. I want to access it through a UI button click, (for the sake of getting it to work I am experimenting using spacebar instead) and I am not clear on how to get it to set the bool to true in script (C#)

I am here in my effort

using UnityEngine;
using System.Collections;

public class expandDV : MonoBehaviour
{
Animator anim;

void Start ()
	{
			anim = GetComponent<Animator> ();
	}

void Update ()
	{
			//AnimatorStateInfo stateInfo = anim.GetCurrentAnimatorStateInfo (0);
			if (Input.GetKeyDown (KeyCode.Space)) 
					anim.SetBool (expand = true);
	}

}

apologies for my noob-ness

Thanks

I think you want to use:

anim.SetBool("expand", true);