• python基本数据类型操作


    str 字符串 

    #1.进行字符串转换 首字母转换成大写
    # name = 'wangjianhui'
    # v = name.capitalize()
    # print(v)
    
    #2. 字符转换小写
    # name = 'WangJianHui' #将所有的字符串转换成小写 包括多种语言
    # v = name.casefold()
    # print(v)
    # name = 'WangJianHui' #将所有字符转换成小写,只限于英文
    # v = name.lower()
    # print(v)
    
    #3 填充空白
    # name = 'wangjianhui'  #填充空白 将字符串内容居中
    # v = name.center(50,'*')
    # print(v)
    
    #4 查询索引
    # name = 'wangjianhui123321' 查询出现字符的次数
    # v = name.count('1')
    # v = name.count('wang',0,15)指定查询位置以某索引开始到某索引结束
    # print(v)
    
    #5查询是否已某字段开始或结束
    # name = 'wangjianhui'
    # v = name.endswith('hui')
    # print(v)
    # v = name.startswith('wang')
    
    #6 找到制表符	,进行替换(包含前面的值)
    # name = 'name:	wangjianhui
    age:	19'
    # v = name.expandtabs(10)#
    # print(v)
    
    #7 查询索引位置
    # name = 'wangjianhui'
    # v = name.index('w') 字符串中不存在的内容 查找会报错
    # print(v)
    # v = name.find('w') 字符串不存在的内容 查找返回-1
    # print(v)
    
    #8 字符串格式化方法
    # infomesion = 'name:%sage:%sjob:%s'  %s占位符
    # print(infomesion%('wangjianhui',19,'it'))
    
    # infomesion = 'name:{0};age:{1};job{2}' format方法
    # v = infomesion.format('wangjianhui',19,'it')
    # print(v)
    # infomesion = 'name:{name};age:{age};job{nianling}'
    # v = infomesion.format(name='wangjianhui',age=19,nianling='it')
    # print(v)
    
    # infomesion = 'name:{name};age:{age};job{nianling}' format_map 以字典的形式进行填充
    # v = infomesion.format_map({'name':'wangjianhui','age':19,'nianling':'it'})
    # print(v)
    
    #9字符串内容进行判断
    #是否是数字、汉字不能包含特殊符号
    # name = 'wangjianhui男子汉1'
    # v = name.isalnum()
    # print(v)
    #判断是否是数字
    # name = ''
    # v1 = name.isdecimal() #只能判断是否为阿拉伯数字
    # v2 = name.isdigit() #特殊数字如②也可识别
    # v3 = name.isnumeric()#阿拉伯数字及② 二都可识别
    # print(v1,v2,v3)
    
    #10
    #判断是否是标识符
    # name = 'wangjianhui'
    # v = name.isidentifier()
    # print(v)
    
    #11
    #判断是否全部是小写
    # name = 'WangJianHui'
    # v1 = name.islower()
    # v2 = name.isupper()
    # print(v1,v2)
    
    #12
    #全部变大写 对应全部小写lower
    # name = 'wangjianhui'
    # v = name.upper()
    # print(v)
    
    
    # 13
    # 是否包含隐含的xx
    # name = "钓鱼要钓刀鱼,
    刀鱼要到岛上钓"
    # v = name.isprintable()
    # print(v)
    
    # 14
    # 是否全部是空格
    # name = '    '
    # v = name.isspace()
    # print(v)
    
    #15
    #内部循环每个元素
    # name = 'wangjianhui'
    # v = '_'.join(name)
    # print(v)
    # name = ['王建辉','金丽珍']
    # v = ''.join(name)
    # print(v)
    
    #16
    #字符替换
    # name = 'aleX'
    # v = name.replace('l','p')
    # print(v)
    
    #17
    #转换字节类型
    # name = '王建辉'
    # v1 = name.encode(encoding='utf-8')
    # v2 = name.encode(encoding='gbk')
    # print(v1,v2)
    
    #18左右填充
    # center,rjust,ljust
    # name = 'wangjianhui'
    # v = name.ljust(20,'*')
    # print(v)
    
    #19对应关系加翻译
    # m = str.maketrans('wangjianhui','123456')
    # name = 'wangxiaoerweqrrwrwrq;wfasfs'
    # v = name.translate(m)
    # print(v)
    
    #20保留分割的元素
    # content = "李泉SB刘康SB刘浩SB刘一"
    # v = content.replace('SB','Love')
    # print(v)
    # v = content.replace('SB','Love',1) 指定几个字符替换
    # print(v)
    
    # 21,移除空白,
    ,	,自定义
    # name = 'alex	'
    # v = name.strip() # 空白,
    ,	
    # print(v)
    
    # 22. 大小写转换
    # name = "Alex"
    # v = name.swapcase()
    # print(v)
    
    #23填充0
    # name = 'wangjianhui'
    # v = name.zfill(30)
    #
    # name1 = 'wangjianhui1'
    # v = name + name1
    # print(v)
    
    ###### 字符串功能总结:
    # name = 'alex' 创建字符串给变量 或str()
    # name.upper()  转换为大写
    # name.lower()转换为小写
    # name.split() 切割
    # name.find() 查找索引 没有不会报错
    # name.strip() 移除空白或指定符号
    # name.startswith()以什么内容开始
    # name.format() 表格填充
    # name.replace() 保留分割元素替换
    # "alex".join(["aa",'bb']) 添加分割
    
    ###### 额外功能:
    # name = "alex"
    # name[0]
    # name[0:3]
    # name[0:3:2]
    # len(name)
    # for循环,每个元素是字符
    # for i len(name):
    #     print(name[i])

     

    int 整数

    #1. 获取当前数值二进制最小位数
    # name = 10
    # v = name.bit_length()
    # print(v)
    
    #2.获取当前数据的字节表示
    # name = 15
    # v = name.to_bytes(5,byteorder='big') #位数表示 从后往前正常显示
    # v1 = name.to_bytes(5,byteorder='little')#从前往后反向显示
    # print(v,v1)

     

    bool 布尔值

    #1. False True
    #0为False 1或其他为True
    # print(bool(0))


    list 列表

    # user_list = ['李泉','刘一','刘康','豆豆','小龙'] # 可变类型
    # PS:
    #功能集合
    #1.追加 append
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # user_list.append('王二')
    # print(user_list)
    
    #2.清空 clear
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # user_list.clear()
    # print(user_list)
    
    #3.拷贝 浅拷贝copy
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # user_list1 = user_list.copy()
    # print(user_list1)
    
    #4.计数 统计某个列表字符数量 count
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # user_c = user_list.count('小龙')
    # print(user_c)
    
    #5.扩展列表 extend
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # user_list.extend(['王建辉','王二小'])
    # print(user_list)
    
    #6.查找元素索引,没有则报错 index
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # v = user_list.index('小龙')
    # print(v)
    
    #7.删除 pop(按照索引删除,并保存删除值) remove(指定删除内容不保存) del(索引删除不保留)
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # v = user_list.pop(1)
    # print(v,user_list)
    
    # del user_list[1]
    # print(user_list)
    
    # user_list.remove('李泉')
    # print(user_list)
    
    #8.列表翻转 reverse
    # user_list = ['李泉','刘一','刘康','豆豆','小龙']
    # user_list.reverse()
    # print(user_list)
    
    #9.排序 sort
    #user_list = [1,'李泉','刘一','刘康','豆豆','小龙']#数字和字符不能进行排序
    # user_list = [10,20,5,67,44]
    # user_list.sort() #从小到大
    # print(user_list)
    # user_list.sort(reverse=True/False) 从大到小或从小到大
    # print(user_list)
    
    #10.
    
    ######  额外:
    # user_list = ['李泉','刘一','李泉','刘康','豆豆','小龙']
    # user_list[0]
    # user_list[1:5:2] #显示从索引开始结束 跳着显示
    # del user_list[3]
    # for i in user_list: #循环显示
    #     print(i)
    # user_list[1] = '姜日天' 覆盖或修改
    # user_list = ['李泉','刘一','李泉','刘康','豆豆',['日天','日地','泰迪'],'小龙'] #嵌套

    range,enumrate

    # 1. 请输出1-10
    # 2.7: 立即生成所有数字
    # range(1,11) # 生成 1,23,,4,56.10
    
    # 3.x: 不会立即生成,只有循环迭代时,才一个一个生成
    # for i in range(1,11): #
    #     print(i)
    
    # for i in range(1,11,2): #
    #     print(i)
    
    # for i in range(10,0,-1): #
    #     print(i)
    
    # 2. range: 三个参数
    #
    # li = ['eric','alex','tony']
    # # range,len,li循环
    # for i in range(0,len(li)):
    #     ele = li[i]
    #     print(ele)
    
    
    # li = ['eric','alex','tony']
    # for i in li:
    #     print(i)
    
    # for i in range(0,len(li)):
    #     print(i+1,li[i])
    
    # enumerate额外生成一列有序的数字
    # li = ['eric','alex','tony']
    # for i,ele in enumerate(li,1):
    #     print(i,ele)
    #
    # v = input('请输入商品序号:')
    # v = int(v)
    # item = li[v-1]
    # print(item)

    tuple:元组,不可被修改的列表;不可变类型

    #创建元组
    #name = ('wnagjianhui','wangxiaoer','wangerxiao')
    #1.获取元祖字符个数
    # name = ('wangjianhui','wangxiaoer','wangerxiao')
    # v = name.count('wangjianhui')
    # print(v)
    
    #2.获取索引位置
    # name = ('wangjianhui','wangxiaoer','wangerxiao')
    # v = name.index('wangjianhui')
    # print(v)
    
    #3.额外
    # user_tuple = ('alex','eric','seven','alex')
    # for i in user_tuple:
    #     print(i)
    
    # v = user_tuple[0]
    
    # v = user_tuple[0:2]
    # print(v)
    
    # user_tuple = ('alex','eric','seven',['陈涛','刘浩','赵芬芬'],'alex')
    # user_tuple[0] = 123   x
    # user_tuple[3] = [11,22,33] x
    # user_tuple[3][1] = '刘一'
    # print(user_tuple)
    
    # li = ['陈涛','刘浩',('alex','eric','seven'),'赵芬芬']
    # ****** 元组最后,加逗号 ******
    # li = ('alex',)
    # print(li)

    dict:字典: 可变类型

    #1.清空字典 clear
    # namedic = {'name':'wangjianhui','age':19,'job':'it'}
    # namedic.clear()
    # print(namedic)
    
    #2.浅拷贝 copy
    # namedic = {'name':'wangjianhui','age':19,'job':'it'}
    # namedic1 = namedic.copy()
    # print(namedic1)
    
    #3.根据key值获取value值,不存在不报错 get
    # namedic = {'name':'wangjianhui','age':19,'job':'it'} get查找根据key找value 找不到不报错
    # namedic1 = namedic.get('name')
    # print(namedic1)
    
    #4.删除key对应的value值 并保存删除值
    # namedic = {'name':'wangjianhui','age':19,'job':'it'}
    # namedic1 = namedic.pop('name')
    # print(namedic1,namedic)
    
    # 5. 随机删除键值对,并获取到删除的键值 popitem
    # dic = {'k1':'v1','k2':'v2'}
    # v = dic.popitem()
    # print(dic)
    # print(v)
    
    # v = dic.popitem() # ('k2', 'v2')
    # print(dic)
    # print(v[0],v[1])
    
    #6.增加字典 如果存在则不作操作
    # namedic = {'name':'wangjianhui','age':19,'job':'it'}
    # namedic.setdefault('wait','1111')
    # print(namedic)
    
    #7.批量增加或修改
    # namedic = {'name':'wangjianhui','age':19,'job':'it'}
    # namedic.update({'name':'wangxiaoer','wait':'111'})
    # print(namedic)
    
    #8.批量创建字典
    # dic = dict.fromkeys(['k1','k2','k3'],321)
    # print(dic)
    
    # ########## 额外:
    # - 字典可以嵌套
    # - 字典key: 必须是不可变类型
    # dic = {
    #     'k1': 'v1',
    #     'k2': [1,2,3,],
    #     (1,2): 'lllll',
    #     1: 'fffffffff',
    #     111: 'asdf',
    # }
    # print(dic)
    # key:
    #     - 不可变
    #     - True,1
    
    # dic = {'k1':'v1'}
    # del dic['k1']

    set集合

    # s1 = {"alex",'eric','tony','李泉','李泉11'}
    # s2 = {"alex",'eric','tony','刘一'}
    # 1.s1中存在,s2中不存在
    # v = s1.difference(s2)
    # print(v)
    # #### s1中存在,s2中不存在,然后对s1清空,然后在重新复制
    # s1.difference_update(s2)
    # print(s1)
    
    # 2.s2中存在,s1中不存在
    # v = s2.difference(s1)
    # print(v)
    
    # 3.s2中存在,s1中不存在
    # s1中存在,s2中不存在
    # v = s1.symmetric_difference(s2)
    # print(v)
    # 4. 交集
    # v = s1.intersection(s2)
    # print(v)
    # 5. 并集
    # v = s1.union(s2)
    # print(v)
    
    # 6. 移除
    # s1 = {"alex",'eric','tony','李泉','李泉11'}
    # s1.discard('alex')
    # print(s1)
    
    # s1 = {"alex",'eric','tony','李泉','李泉11'}
    # s1.update({'alex','123123','fff'})
    # print(s1)
    # ##### 额外:
    
    # s1 = {"alex",'eric','tony','李泉','李泉11'}
    # for i in s1:
    #     print(i)
    
    # s1 = {"alex",'eric','tony','李泉','李泉11',(11,22,33)}
    # for i in s1:
    #     print(i)
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  • 原文地址:https://www.cnblogs.com/dahuige/p/13963718.html
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