字符串、列表及元组均可通过“+”号进行拼接,但要求同种类型数据之间才能拼接
#字符串拼接 a = "Hello" b = ",Python" print(a + b) #列表拼接 li1 = ["I"] li2 = ["Love","Python"] print(li1 + li2)字符串、列表及元组均可通过“*”号进行重复输出
#字符串重复 a = "City_college " print(a * 3) #列表重复 li2 = ["Love","Python"] print(li2 * 3)字符串、列表及元组均可通过“[:],[::]”进行部分输出
str = "Python" print(str[2]) #遍历数组 for i in range(len(str)): print(str[i],end="") for char in str: print(char,end = "") #切片 str = "life is short,you need python." print(len(str)) print(str[:4]) #翻转输出 str = "life is short, you need python." print(len(str)) print(str[::-1]) #列表索引,切片 li = ['C','i','t','y',"city",'college','zhengjiang'] print(len(li)) print((li[0],li[-7])) print(li[:5])字符串、列表及元组均可通过- count()函数对指定元素进行计数
#字符串计数 str = "LIFE is short, you NEED python." print(str.count("o",9,17)) #指定范围内查找指定的参数 #列表计数 li = ['a','b','c','d','e','city','e'] print(li.count('e'))字符串,列表及元组均可通过三种方式进行遍历
(1)元素遍历
li = ['a','b','c','d','e','city','e'] for char in li: print(char)(2)索引遍历
li = ['a','b','c','d','e','city','e'] for i in range(len(li)): print(li[i])(3)枚举遍历
- enumerate() #对于一个可迭代的/可遍历的对象(如列表,字符串等),enumerate()将其组成一个索引序列,利用它我们可以获得索引和值 li = ['a','b','c','d','e','city','e'] for i in enumerate(li,2): print(i)(1)字符串创建:用引号(“ ”)来创建字符串
name = "hangzhou" area = "gongshu" history = "2000" person = """苏轼,许仙,白素贞""" captical_of = '''吴越,南宋''' sent = "i'm lilei" sent2 = '"He is my brother",he said' sent3 = '''轻轻地我走了, 正如我轻轻地来。'''(2)大小写转换:
str = "LIFE is short, you NEED python." print(str.lower()) #转小写 print(str.upper()) #转大写 print(str.swapcase()) #大小写互换 print(str.title()) #转为标题形式 print(str.capitalize()) #首字母大写(3)删除指定字符:
str.strip() #删除两边指定字符 str.lstrip() #删除左边指定字符 str.rstrip() #删除右边指定字符(4)字符串搜索定位和替换
str.find() #查找元素并返回第一次出现时的索引值,查找不到返回-1 str.rindex() #从右往左查找 str.replace([现有字符],[替换字符])(5)字符串条件判断
str.isalnum() #判断字符串有字母或者数字组成 str.isalpha() #判断仅有字母组成 str.isdigit() #判断仅有数字组成(6)字符串的分割变换
"字符".join(str) #将指定字符插入到元素之间 str.split("字符") #以指定字符分割并去除该字符 str.partition("字符") #以指定字符分割字符串并保留字符(7)ASCII值和字符的转化
chr() #digit--->alpha ord() #alpha--->digit(1)列表创建:用方括号括起来的[],每个元素以逗号分隔
#创建空列表 li = [] print(type(li)) #创建多元素列表 li = [1,2,3,"abcd","City","College",["I","Love","Python"]](2)增删改查
# 1.增 - append() - extend() #取出元素再添加 - insert() #按照索引添加 li = ["City","College"] print((id(li))) li1 = ["a","b","c"] li.append(li1) print(li) print(id(li)) li = ["City","College"] li1 = ["a","b","c"] li.extend(li1) print(li) li = ["City","College"] li1 = ["a","b","c"] li.insert(1,li1) print(li) # 2.改 li = ["City","College","a","b","c"] li1 = ["a","b","c"] li[4] = "6666" li[2:4] = ["x","y","z"] print(li) #3.删除 - pop() #如果不指定索引,默认删除最后一个元素 li = ['a','b','c','d','e'] print(li.pop(2)) print(li) - remove() #移除第一次遇到的指定元素 li = ['a','b','c','d','e','city','e'] print(li.remove("e")) print(li) - del() li = ['a','b','c','d','e','city','e'] del li[5] print(li) - clear() #清空列表 li = ['a','b','c','d','e','city','e'] li.clear() print(li) # 4.查 --->索引,切片(1)元组创建:用括号括起来的(),每个元素以逗号分隔,单个元素的元组需在单元素后添加逗号
tp = ("abc",) tp = tuple() tp = ("abc") #此时tp为字符串(2)删除
元组不可改变,只能通过del进行全部删除,不能删除指定元素