✔ 最佳答案
You don't need visa if you are planning to stay less than 30 days
http://www.boca.gov.tw/ct.asp?xItem=1443&ctNode=116&mp=2 ( it can't postpone).
If you are planning to stay in Taiwan over 30 days, you have to apply it before you get in to Taiwan (usually you need to apply it in Canada's embassies
http://www.boca.gov.tw/ct.asp?xItem=1564&ctNode=125&mp=2 ).
參考: I have had the same situation :p