Python学习第三天

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# 6 expandtabs,断句20,

# test = "username email password laiying ying@q.com 123 laiying ying@q.com 123 laiying ying@q.com 123"
# v = test.expandtabs(20)
# print(v)

# 12 是否是字母,汉字

# test = "as2df"
# v = test.isalpha()
# print(v)

# 13 当前输入是否是数字

# test = "二" # 1,②
# v1 = test.isdecimal() #十进制
# v2 = test.isdigit() #可以识别特殊数字
# v3 = test.isnumeric() #可以包含汉字的数
# print(v1,v2,v3)


# 14 是否存在不可显示的字符

# 制表符
# 换行
# test = "oiuas dfkj"
# v = test.isprintable()
# print(v)

# 15 判断是否全部是空格

# test = ""
# v = test.isspace()
# print(v)

# 16 判断是否是标题 (所有单词首字母大写)

# test = "Return True if all cased characters in S are uppercase and there is"
# v1 = test.istitle()
# print(v1)
# v2 = test.title()
# print(v2)
# v3 = v2.istitle()
# print(v3)

# 17 ***** 将字符串中的每一个元素按照指定分隔符进行拼接

# test = "你是风儿我是沙"
# print(test)
# # t = ‘ ‘
# v = "_".join(test)
# print(v)

# 18 判断是否全部是大小写 和 转换为大小写

# test = "Alex"
# v1 = test.islower()
# v2 = test.lower()
# print(v1, v2)

# v1 = test.isupper()
# v2 = test.upper()
# print(v1,v2)

# 19 # 移除指定字符串 # 有限最多匹配

# test = "xa"
# # v = test.lstrip(‘xa‘)
# v = test.rstrip(‘9lexxexa‘)
# # v = test.strip(‘xa‘)
# print(v)

# test.lstrip()
# test.rstrip()
# test.strip()
# 去除左右空白
# v = test.lstrip()
# v = test.rstrip()
# v = test.strip()
# print(v)
# print(test)
# 去除
# v = test.lstrip()
# v = test.rstrip()
# v = test.strip()
# print(v)

# 20 对应关系替换

# test = "aeiou"
# test1 = "12345"

# v = "asidufkasd;fiuadkf;adfkjalsdjf"
# m = str.maketrans("aeiou", "12345")
# new_v = v.translate(m)
# print(new_v)

# 21 分割为三部分

# test = "testasdsddfg"
# v = test.partition(‘s‘)
# print(v)
# v = test.rpartition(‘s‘)
# print(v)

# 22 分割为指定个数

# v = test.split(‘s‘,2)
# print(v)
# test.rsplit()


# 23 分割,只能根据,true,false:是否保留换行

# test = "asdfadfasdf asdfasdf adfasdf"
# v = test.splitlines(False)
# print(v)

# 24 以xxx开头,以xx结尾

# test = "backend 1.1.1.1"
# v = test.startswith(‘a‘)
# print(v)
# test.endswith(‘a)

# 25 大小写转换

# test = "aLex"
# v = test.swapcase()
# print(v)

# 26 字母,数字,下划线 : 标识符 def class

# a = "def"
# v = a.isidentifier()
# print(v)


# 27 将指定字符串替换为指定字符串

# test = "alexalexalex"
# v = test.replace("ex",‘bbb‘)
# print(v)
# v = test.replace("ex",‘bbb‘,2)
# print(v)


###################### 7个基本魔法 ######################

# join # ‘_‘.join("asdfasdf")
# split
# find
# strip
# upper
# lower
# replace
###################### 4个灰魔法 ######################
# test = "郑建文妹子有种冲我来"

# 一、for循环

# for 变量名 in 字符串:
# 变量名
# break
# continue


# index = 0
# while index < len(test):
#    v = test[index]
#   print(v)
#   index += 1
# print(‘=======‘)

# for zjw in test:
#    print(zjw)

# test = "郑建文妹子有种冲我来"
# for item in test:
#    print(item)
#    break

# for item in test:
#    continue
#    print(item)

# 二、索引,下标,获取字符串中的某一个字符

# v = test[3]
# print(v)

# 三、切片

# v = test[0:-1] # 0=< <1 #-1表示最后一个位置
# print(v)

# 四、获取长度

# Python3: len获取当前字符串中由几个字符组成
# v = len(test)
# print(v)

# 注意:
# len("asdf")
# for循环
# 索引
# 切片

# 五、获取连续或不连续的数字,

# Python2中直接创建在内容中
# python3中只有for循环时,才一个一个创建
# r1 = range(10)
# r2 = range(1,10)
# r3 = range(1,10,2)
# 帮助创建连续的数字,通过设置步长来指定不连续
# v = range(0, 100, 5)
#
# for item in v:
# print(item)

##### 练习题:根据用户输入的值,输出每一个字符以及当前字符所在的索引位置 #####
# test = input(">>>")
# for item in test:
# print(item)

# 将文字 对应的索引打印出来:
# test = input(">>>")
# print(test) # test = qwe test[0] test[1]
# l = len(test) # l = 3
# print(l)
#
# r = range(0,l) # 0,3
# for item in r:
#   print(item, test[item]) # 0 q,1 w,2 e

# test = input(">>>")
# for item in range(0, len(test)):
#   print(item, test[item])

 

###################### 1个深灰魔法 ######################

# 字符串一旦创建,不可修改
# 一旦修改或者拼接,都会造成重新生成字符串

# name = "zhengjianwen"
# age = "18"
#
# info = name + age
# print(info)

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