as后面的代词用主格还是宾格

回答如下：

(1)如果as作为介词使用，其后的代词需要使用宾格

They regard the boy in the picture as me.

他们把照片中的那个男孩当作是我了.

(2)如果as作为连词使用，其后的代词需要使用主格

I was coming in as he was going out.   
我进来的时候,他正出去。

My pen trembles as I write it.   
我一边写,笔一边颤抖。

Helen heard the story as she washed.   
海伦洗衣服的时候听了这个故事

As I left the huose I remembered the key.   
当我离开房间的时候,我想起了钥匙。

As I was coming here,I met your brother.   
我来这儿的时候遇见了你哥哥。

The boy's eyes had slowly moved to him as he had spoken.   
他说完时,这孩子的眼光已慢慢地移到他身上。

I can't come tonight,as I'm going to a concert.   
今晚我不能来,因为我要去听音乐会。

I am going to bed,as I am very tired.   
我疲倦得很，要去睡了。

As you can see, we're still working.

如你所见，我们仍在工作。

We were sitting, as I remember, in a riverside restaurant.

我记得我们当时是坐在一个河畔的餐馆里。

继续跟踪回答如下

He has the same hobby as I 还是as me?

He has the same hobby as I (do)（为正确）

原因是后面省略（谓语+宾语结构），需要填主格代词作主语.

(1)He works in the same company as I do.

(2)Mary used the same book as I do.

(3)The coffee is the same as we had at Tom's.