It's a gentle way of breaking no to the other party. It's encouraging as it lets the person know you like the idea (of course, only say this if you do like it) and there's nothing wrong about it.
这是一种委婉拒绝他人的方式。这句话比较鼓舞人心，因为它让对方知道你愿意做这事（当然，只有当你真的愿意的时候才请这样说），并且他/她的请求本身没有什么不对。