python字符串的含义

#!/usr/bin/python3
name="my    name is xiAngXiao"
name2="alex"
name3="my {name} is xiangxiao,and my {yeae} is"
#print(name.capitalize())#将首字母都大写
#print(name.center(50,"-"))#name放中间，两边加上-符号
#print(name2.endswith(ex))#判断name2是否以ex结尾
#print(name.expandtabs(tabsize=50))#将tab键转换成多少个空格
#print(name.find("y"))#返回y的位置
#print(name[name.find("y"):9])#从y的位置到9之前的所有字符
#print(name3.format(name='xiangxiao',yeae=26))#格式化并且赋值
#print(name.format_map({'name':'alex','yeae':26}))
#print('abc123'.isalnum())#判断是否包含字符和数字，返回True，如果有特殊字符返回false
#print('abA'.isalpha())#纯英文字符，大小写均可
#print('1A'.isdecimal())#十进制的判断
#print('1'.isdigit())#判断是否是数字
#print('1A'.isidentifier())#标示符的判断
#print('33'.isnumeric())#判断是否有小数点
#print('My Name IS'.istitle())#首写字符是否大写
#print(','.join(['1','2','3']))#将中括号中的内容加到单引号，并且用都好隔开
#print(name.ljust(50,'*'))#名字在左边，右边用*号补齐够50个
#print(name.rjust(50,'*'))#名字在右边，左边用*号补齐
#print('Alex'.lower())#所有字母小写
#print('Alex'.upper())#所有字母大写
#print('Alex\n'.lstrip())#去掉左边的空格和回车
#print('\nAlex'.rstrip())#去掉右边的空格和回车
#print('\nAlex\n'.strip())#去掉空格和回车
#print('---')
#p=str.maketrans("abcefg","123456")
#print("xiangx".translate(p))#将对应的字母翻译成数字
#print('xiangxiao'.replace('x','X',1))#将第一个小写x改成大写X
#print('xiangxiao'.rfind('x'))#返回最后一个x的位置
#print('1+2+3+4'.split('+'))#以+号为分隔符，
#print('1+2\n+3+4'.splitlines())#以\n为分隔符
#print('xiangxiao'.title())#首写字母大写
#print('lexli'.zfill(50))#用0填充左边

 

字典的使用：

例：

info={

“stu1001”:”wangbo”,

“stu1002”:”xiangxiao”,

“stu1003”:”xiongyuhang”

}

b={“stu1101”:”alex”,1:2,3:4}

#print(info) #打印字典

c=dic.fromkeys([6,7,8],”test”)#中括号是key,双引号对应取值

c=dic.fromkeys([6,7,8],[1,{“name”:”alex”},2])

c[7][1][“name”]=”jackchen”#将alex的改为jackchen

for i in info:

print(i,info[i])

例2：三级菜单：

 

data={'广州':{'天河':['天河体育馆','天河大厦'],#初始化地名
                    '越秀':['越秀公园','光孝寺'],
                    '番禹':['长龙幻世界','大夫山']},
           '陕西':{'西安':['长安','雁塔'],
                    '商洛':['商南','山阳'],
                    '汉中':['汉台','南镇']},
            '上海':{'浦东':['枫桥','孔庙'],
                    '南海':['千灯湖','南国桃园'],
                    '顺德':['清晖园','西山庙']}}
ex_flag=False
while not ex_flag:
    for i in data:
        print(i)
    choice=input("请选择地方>>")
    if choice in data:
        while not ex_flag:
            for i2 in data[choice]:
                print("\t",i2)
            choice2=input("请选择地方2>>")
            if choice2 in data[choice]:
                while not ex_flag:
                    for i3 in data[choice][choice2]:
                        print("\t\t",i3)
                    choice3=input("请选择地方3>>")
                    if choice3 in data[choice][choice2]:
                        pass
                    if choice3=="b":
                        break
                    if choice3=="q":
                        ex_flag=True

            if choice2=="b":
                break
            elif choice2=="q":
                ex_flag=True
    if choice=="q" :
        ex_flag=True