python-字符串 列表 字典

字符串

字符串

创建

a = "make"
a = str('alex')

转换

age = 19
new_age = str(age)

字符串的拼接

name = "make"
gender = "男"
new_str = name + gender
print(new_str)

占位符

nam = "我叫smkf，性别：%s，年龄：%s" % ('nan',19)
print(nam)

字符串功能

移除空白

val  = '   make'
print(val)
new_val = val.strip()   #移除空白
new_val = val.lstrip()   #移除左边空白
new_val = val.lstrip()   #移除右边空白

　分隔

v = 'make|hello|123'
new_v = v.split("|",1)
new_v = v.rsplit("|",1)  #从右边分隔
print(new_v)

长度(指字符长度)

a = "李白"
print(len(a))

索引

a = "李白"
print(a[0])

切片

val[::]

---

列表

---

字典

字典操作

v = {
    'name':'make',
    'age':19
}

#查找
n = v["name"]
print(n)
#增加： 有-增加； 没有-修改
v['passwd']=123     #如果没有就是增加如果有就是修改
print(v)
#删除
del v['name']
print(v)
#遍历k
for item in v.keys():
    print(item)
#遍历v
for item in v.values():
    print(item)
#遍历k,v
for k,v in v.items():
    print(k,v)

列表字典嵌套

user_dict = {
    'k1':'v1',
    'k2':{'kk1':'vv1','kk2':'vv2'},
    'k3':123,
    'k4':['alex','edc',['a','b','c'],'MAKE',{'a':'A'}],
}

user_dict['k4'][2].append('aa')
user_dict['k4'][4]['n']="N"

print(user_dict)

#!/usr/bin/python
# -*- coding:utf-8 -*-
user  = input("输入名字")
passwd = input('输入密码')
user_list=[
    {'name':"mk",'passwd':'123','times':1},
    {'name':"lcf",'passwd':'456','times':1}
]
for item in user_list:
    if user == item['name'] and passwd == item['passwd']:
        print('登录成功！')
    

转载于:https://www.cnblogs.com/ma-ke/p/6853024.html