应该不相等，因为don't have to do sth是客观说法，茄洞滚颤饥而don't need to do sth则是主观颤余说法，
以上纯属个人见解哦，你还是查一下吧
don't have to do sth
don't need to do sth
needn't do sth
一般来说是一样、并可互帆镇陵换的
The teacher says you don't have to do it
The teacher says you don't need to do it
The teacher says you needn't do it
异曲态戚同工。
（这不是主观 和客观旅盯的问题。）
don't have to do sth不是必须做某哪瞎事数缓备
don't need to do sth 不需要薯毁做某事
needn't do sth不需要做某事
don't have to do sth 不是纯培必须做，
don't need to do sth 和needn't do sth 不必要做巧裤银，没必要做孝宴