python-day2
# python中的索引与切片# 1.索 引：
# str = 'mixuebingcheng'
# print(str) # m
# print(str[-1]) # g
# print(str) # string index out of range 索引跨界
# print(str[-14]) # m
# print(str[-15]) # string index out of range 索引跨界
#
# 2.切 片：
# 默认是正步长
# str = 'mixuebingcheng'
# print(str) # mixuebin
# print(str[:8]) # mixuebin
# print(str) # gcheng
# print(str) # chen
# ------------------------------------------------
# print(str[:-14:-1]) # gnehcgnibeuxi
# print(str[-1:-10:-1]) # gnehcgnib
# print(str)# im
# print(str[-1::-1]) # gnehcgnibeuxim
# print(str[::-1]) # gnehcgnibeuxim
#
#3.跳 切
# str = 'mixuebingcheng'
# print(str) # iubn
# print(str[::2]) # mxeighn
# print(str) # mbh
# ----------------------------------
# print(str[-1:-14:-2]) # gecnbui
# print(str[::-2]) # gecnbui
# print(str[::-5]) # ggu
# python中的字符串函数
# 1.capitaliz() 首字符大写
# str = 'xiaozhang'
# print(str.capitalize()) # Xiaozhang
# str = 'xiao zhang'
# print(str.capitalize()) # Xiao zhang
# 2.title()函数 标题化字符串，首字母大写、其余的小写
# str = 'xiaozhang'
# print(str.title()) # Xiaozhang
# str = 'xiao zhang'
# print(str.title()) # Xiao Zhang
# 3.count() 统计具体字符出现的次数
# str = 'xiaozhang'
# print(str.count('a')) # 2
# 4.join() 把序列中的字符按自定义的分隔符连接起来
# str = 'xiaozhang'
# print('-'.join(str)) # x-i-a-o-z-h-a-n-g
# print('*'.join(str)) # x*i*a*o*z*h*a*n*g
# print(''.join(str)) # xiaozhang
#5.split() 把字符串通过指定标识进行分割
# str = 'xiao zhang'
# list = str.split(' ')
# print(list) # ['xiao', 'zhang']
# print(type(list)) # <class 'list'>
#
# print(list) # xiao
# print(list) # zhang
# print(''.join(list)) # xiaozhang
# 练 习
# 把字符串user_name输出为UserName
# str1 = 'user_name'
# print(str1.title()) # User_Name
# str2 = str1.title()
# list1 = str2.split('_')
# print(list1) # ['User', 'Nameh']
# list2 = list1+list1
# print(list2) # UserName
# 6.strip(ab) 删除字符串开头和结尾有a或b字符
# str1 = 'duoceshiud'
# print(str1.strip('du')) # oceshi
# print(str1.strip('ud')) # oceshi
# print(str1.strip('u')) # duoceshiud
# 7.lstrip(ab) 删除字符串开头的有ab的字符串
# str1 = 'duoceshiud'
# print(str1.lstrip('du')) # oceshiud
# print(str1.lstrip('ud')) # oceshiud
# print(str1.lstrip('u')) # duoceshiud
# 8.rstrip(ab)删除字符串结尾的有ab的字符串
# str1 = 'duoceshiud'
# print(str1.rstrip('du')) # duoceshi
# print(str1.rstrip('ud')) # duoceshi
# print(str1.rstrip('u')) # duoceshiud
# 9.startswith()判断字符是以什么开头，输出布尔值
# str1 = 'duoceshi'
# print(str1.startswith('du')) # True
# print(str1.startswith('ud')) # False
# 10.endswith() 判断字符是以什么结束的，输出布尔值
# str1 = 'duoceshiud'
# print(str1.endswith('ud')) # true
# print(str1.endswith('du')) # false
# endswith()应用
# file_name = input('请输入您的文件名称:')
# if file_name.endswith('.py'):
# print('输入正确')
# else:
# print('输入错误')
# 11.find()字符串从左边开始查找，结果显示下索引
# str = 'xiao zhang'
# print(str.find('a')) # 2
# 12.rfind() 字符串从右边开始查找，结果显示下索引
# str = 'xiao zhang'
# print(str.find('a')) # 7
# 13.replace('a','e') 替换字符串中的字符
# str = 'xiao zhang'
# print(str.replace('a','e')) # xieo zheng
# 14.lower() 字符串中的字符大写转换为小写
# str = 'XIAO ZHANG'
# print(str.lower()) # xiao zhang
# 15.upper() 字符串中的字符小写转换为大写
# str = 'xiao zhang'
# print(str.upper()) # XIAO ZHANG
# 16.isdigit() 判断字符串是否全为数字，输出为布尔值
# str1 = '123456'
# print(str1.isdigit()) # true
# str1 = '123456a'
# print(str1.isdigit()) # false
# 17.isalpha() 判断字符串是否全为字母，输出为布尔值
# str1 = 'qwert'
# print(str1.isalpha()) # true
# str1 = 'qwert1'
# print(str1.isalpha()) # false
# 18.isalnum() 判断字符串是否全为数字、字母或者是数字与字母组合
# str1 = 'qwert123'
# print(str1.isalnum()) # true
# str1 = 'qwert123在'
# print(str1.isalnum()) # true
# str1 = 'qwert123_'
# print(str1.isalnum()) # false
# 19.istitle() 判断字符串中首字母为大写，其余是否为小写
# str = 'Xiao zhang'
# print(str.istitle()) # false
# str = 'Xiao Zhang'
# print(str.istitle()) # True
# str = 'xiao zhang'
# print(str.istitle()) # false
# 20.supper() 判断字符串是否全部为大写
# str = 'XIAOZHANG'
# print(str.isupper()) # true
# str = 'XIAOZHANg'
# print(str.isupper()) # false
# 21.islower() 判断字符串是否全部为小写
# str = 'xiaozhang'
# print(str.islower()) # true
# str = 'Xiaozhang'
# print(str.islower()) # false
# python中的列表
# 1.定义列表的第一张方法
# list1 = ['xiaowang','laowang','niuqi',['王大麻子'],'12345']
# print(list1) # ['xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345']
# print(type(list1)) # <class 'list'>
# 2.使用list（）函数进行转换
# str = 'xian05'
# list1 = list(str)
# print(list1) # ['x', 'i', 'a', 'n', '0', '5']
# list1 = ['x', 'i', 'a', 'n', '0', '5']
# str1 = str(list1)
# print(str1) # ['x', 'i', 'a', 'n', '0', '5']
# print(type(str1)) # <class 'str'>
# print(''.join(list1)) # xian05
# 3.列表使用索引赋值
# list1 = ['xiaowang','laowang','niuqi',['王大麻子'],'12345']
# print(list1) # xiaowang
# list1 = 'hello'
# print(list1) # ['hello', 'laowang', 'niuqi', ['王大麻子'], '12345']
# 4.切片赋值
# list1 = 'xian05'
# print(list1) # ['x', 'i', 'a', 'n', '0', '5', 'niuqi', ['王大麻子'], '12345']
# print(''.join(list1)) # xian05
# 5.append()函数给列表中添加新的元素，添加的值都在最末尾
# list1 = ['xiaowang','laowang','niuqi',['王大麻子'],'12345']
# # list1.append('xian05')
# # print(list1) # ['xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345', 'xian05']
# # list1.append(10000)
# # print(list1) # ['xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345', 10000]
# list1.append()
# print(list1) # ['xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345', ]
# 6.insert()函数 根据索引位置去添加新的元素到列表中
# list1 = ['xiaowang','laowang','niuqi',['王大麻子'],'12345']
# list1.insert(1,'dcs')
# print(list1)# ['xiaowang', 'dcs', 'laowang', 'niuqi', ['王大麻子'], '12345']
# list1.insert(1,10086)
# print(list1)# ['xiaowang', 10086, 'laowang', 'niuqi', ['王大麻子'], '12345']
# list1.insert(1,)
# print(list1) # ['xiaowang', , 'laowang', 'niuqi', ['王大麻子'], '12345']
# 7.extend()函数 链接两个列表，传入的值是一个可迭代的对象
# list1 = ['xiaowang']
# list2 = ['dcs']
# str1 = 'pdd'
# int1 = 10010
# list1.extend(list2)
# print(list1) # ['xiaowang', 'dcs']
# list1.extend(str1)
# print(list1) # ['xiaowang', 'p', 'd', 'd']
# list1.extend(int1)
# print(list1) # 'int' object is not iterable
# 8.index()函数查看列表的索引值
# list1 = ['xiaowang','laowang','niuqi',['王大麻子'],'12345']
# print(list1.index('laowang'))# 1
# str = 'xian05'
# print(str.index('a')) # 2
# 9.remove()函数移除列表中的元素---根据列表中的元素值进行删除
# list1 = ['dcs','dcs','xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345']
# list1.remove('dcs') 如果遇见相同元素只能删除第一个
# print(list1) # ['dcs', 'xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345']
# 10.del 使用关键字删除--根据列表中的索引进行删除
# list1 = ['dcs','dcs','xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345']
# del list1
# del list1
# print(list1) # ['xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345']
# del list1
# print(list1) # ['xiaowang', 'laowang', 'niuqi', ['王大麻子'], '12345']
# 11.sort()函数对列表进行排序--默认是升序
# list1 = ['Xiaowang','laowang','niuqi','12345']
# list1.sort()
# print(list1) # ['12345', 'Xiaowang', 'laowang', 'niuqi']
# list2 =
# # list2.sort()
# print(list2) #
# list2.sort(reverse=True)
# print(list2) #
# 12.sorted()函数对列表进行排序
# list1 = ['Xiaowang','laowang','niuqi','12345','20086']
# list2 = sorted(list1)
# print(list2) # ['12345', '20086', 'Xiaowang', 'laowang', 'niuqi']
# list3 = sorted(list1,reverse=True)
# print(list3) # ['niuqi', 'laowang', 'Xiaowang', '20086', '12345']
# 13.revers()函数---反转函数
# list1 = ['Xiaowang','laowang','niuqi','12345','20086']
# list1.reverse()
# print(list1) # ['20086', '12345', 'niuqi', 'laowang', 'Xiaowang']
# print(list1[::-1]) # ['20086', '12345', 'niuqi', 'laowang', 'Xiaowang']
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