GetButton will only play animation when held down

Why not use Mecanim? It's much simpler

I am using mecanim. It's 2D sprite. Anim is a reference to an Animator component. I fixed it my own way. I use coroutine's to detect if an attack is going and it plays the animation.

I see you fixed this your own way, but for reference you should look at how you are handling input:

 // This will play the animation while the button is being held down 
 if (Input.GetButton ("Attack1")&& grounded==true && IsMoving==false) {
              Anim.Play("Attack1");
              IsAttacking=true;
          }
 
 // This will play the animation when the button is pressed
  if (Input.GetButtonDown ("Attack1")&& grounded==true && IsMoving==false) {
              Anim.Play("Attack1");
              IsAttacking=true;
          }
 
 // This will play the animtion when the button is released
  if (Input.GetButtonUp ("Attack1")&& grounded==true && IsMoving==false) {
              Anim.Play("Attack1");
              IsAttacking=true;
          }