Unity3D 物体按键WASD转头并移动

         // 按W键，向上移动
        if (Input.GetKey(KeyCode.W))
        {
            Vector3 e_rot = transform.eulerAngles;
            e_rot.x = -90;
            e_rot.y = 0;
            e_rot.z = 0;
            transform.eulerAngles = e_rot;
            transform.Translate(Vector3.forward * Time.deltaTime * speed, Space.Self);
        }
        // 按S键，向下移动
        else if (Input.GetKey(KeyCode.S))
        {
            Vector3 eulerAngles = transform.eulerAngles;
            eulerAngles.x = 90;
            eulerAngles.y = 0;
            eulerAngles.z = 180;
            transform.eulerAngles = eulerAngles;
            transform.Translate(Vector3.forward * Time.deltaTime * speed, Space.Self);
        }
        // 按A键，向左移动
        else if (Input.GetKey(KeyCode.A))
        {
            Vector3 eulerAngles = transform.eulerAngles;
            eulerAngles.x = 0;
            eulerAngles.y = -90;
            eulerAngles.z = 90;
            transform.eulerAngles = eulerAngles;
            transform.Translate(Vector3.forward * Time.deltaTime * speed, Space.Self);
        }
        // 按D键，向右移动
        else if (Input.GetKey(KeyCode.D))
        {
            Vector3 eulerAngles = transform.eulerAngles;
            eulerAngles.x = 0;
            eulerAngles.y = 90;
            eulerAngles.z = -90;
            transform.eulerAngles = eulerAngles;
            transform.Translate(Vector3.forward * Time.deltaTime * speed, Space.Self);
        }