都可以 只要能听懂就行 你的中文真好 能加好友交流下吗？

When written in Shanghainese, it is similar as marking the sound in roman letters, simply choose a Chinese character has the same pronunciation as the sound you want to express. So wherever you choose it ok if it sounds the same. People identify the sound, not the meaning of the Chinese character. killualaura's suggestion is good, there are some accustomed letters and phrases to follow.

看上去一样不久好了么，格种么最门将就饿

吾就是桑嘿宁，侬刚得老标怎个，吾想帮侬交流交流，吾老想学English,and if you wanna communication with me.I will make a friend with u . We can study each other;-)

推荐 ReTiger 的评论。 由于普通话的推广，很多说方言的朋友不知道自己的语言也有文字，上海话属于吴语，推荐“吴语协会”这个论坛，http://wu-chinese.com