python3字符串base64編解碼

首先，Base64生成的編碼都是ascii字符。

其次，python3中字符都為unicode編碼，而b64encode函數的參數為byte類型，所以必須先轉碼。

s = "你好"

bs = base64.b64encode(s.encode("utf-8")) # 將字符為unicode編碼轉換為utf-8編碼
print(bs) # 得到的編碼結果前帶有 b
>>> b'5L2g5aW9' 

bbs = str(base64.b64decode(bs), "utf-8")
print(bbs) # 解碼
>>> 你好

bs = str(base64.b64encode(s.encode("utf-8")), "utf-8")
print(bs) # 去掉編碼結果前的 b
>>> 5L2g5aW9

bbs = str(base64.b64decode(bs), "utf-8")
print(bbs) # 解碼
>>> 你好