python筆記之字串的使用
阿新 • • 發佈:2018-11-13
# 可以用' '|" "|""" """ 來表示字串 s1 = "你有100w軟妹幣" print(s1) # 需求:你有"100w"軟妹幣 # 利用引號巢狀方式 s2 = '你有"100w"軟妹幣' print(s2) # 利用轉義字元 # \n => 換行符 s3 = "你有\"100w\"軟妹幣" print(s3) # 另外兩種常見的字串表示方式 # r"":原始字串 # 字串中所有合法字元都以原型顯示 s4 = r"你有\"100w\"軟妹幣" # b"":編碼字串 # 編碼解碼 # 知識掃盲:編碼解碼 utf-8 | gbk # 進位制:二進位制 十進位制 十六進位制 s5 = "呵呵" print(s5) # 此時s5 為普通字串 s5 = s5.encode("gbk") # 普通字串可以進行編碼 print(s5) # 此時 s5 為編碼字串 # b'\xba\xc7\xba\xc7' s5 = s5.decode("gbk") # 編碼字串可以進行解碼 print(s5) # 呵呵 # 1011 => 8421 => 8 + 2 + 1 >b # ba =>10111010 s6 = b'\xba\xc7' s6 = s6.decode('gbk') print(s6) # 呵 # + | * | [] |[:] | in |not in # 字串拼接 a = "hello" b = 'world' # hello world res = a + " " + b # 拼接得到的是新字串,原字串資料保留 print(res) # hello world name = "Bob" tag = 1 name = name + str(tag) print(name) # Bob1 # 字串重複 print("*" * 10) # ********** # 取指定索引對應的字元 [] s7 = "今天天氣不好! ai..." print(s7[0]) print(s7[8]) print(s7[-1]) print(s7[-5]) # 今 # a # . # a # 切片;[:] 遵循半閉半開規則 [n,m) 從n取到m ,n <= res < m print(s7[8:]) # 從索引8開始擷取到最後 # ai... print(s7[:-5]) # 從開始擷取到倒數第五位之前 # 今天天氣不好! print(s7[4:6]) # 擷取索引4,5號為字元 # 不好 # 字元存在與否判斷 print("A" in s7) # False print("a" not in s7) # False # upper() | lower() |capitalize()| split() | join() # 全大寫 print("abc".upper()) # ABC # 全小寫 print("XZy".lower()) # xzy # 首字母大寫 print("hello".capitalize()) # Hello # 拆分 #print("name='zero'@age='8'@gender='男'") data = "name='zero'@age='8'@gender='男'" res = data.split("@") print(res) # ["name='zero'", "age='8'", "gender='男'"] # 拼接 # &=> name='zero'&age='8'&gender='男' result = "&".join(res) print(result) # name='zero'&age='8'&gender='男' # 需求:good good study day day up => Good Good Study Day Day Up source = 'good good study day day up' # step1:拆分 s_list = source.split(r' ') print(s_list) # step2:首字母大寫 # 解壓賦值 a,b,c,d,e,f = s_list print(a,b,f) # good good up # a = a.capitalize() a = str(a).capitalize() b = str(b).capitalize() c = str(c).capitalize() d = str(d).capitalize() e = str(e).capitalize() f = str(f).capitalize() # step3: 合併 result = r" " .join([a, b, c, d, e, f]) print(result) # Good Good Study Day Day Up