python基本操作2（速通版）（上）

s1 = "hello"
s2 = '''hello'''
s3 = """hello"""
print(s1*3)
print(s2*3)
print(s3*3)

s = "hello"
#方式1
for c in s:
    print(c)
print("----------------------------------------------")
#方式2
for i in range(len(s)):
    print(s[i])
print("----------------------------------------------")
#方式3
i = 0
while i < len(s):
    print(s[i])
    i += 1
print("----------------------------------------------")

s = '01234567890123456789'
s1 = s[2:4]
print(s1)
print(s)

s = '01234567890123456789'
#s[开头下标:结束下标:步长]
s1 = s[2:4]
print("1:   ",s1)
s1 = s[5:]
print("2:   ",s1)
s1 = s[:10]
print("3:   ",s1)
s1 = s[3:11]
print("4:   ",s1)
#步长
s1 = s[3:11:2]
print("5:   ",s1)
#倒序  这里是左闭右闭区间
s1 = s[10:2:-1]
print("6:   ",s1)
s1 = s[10:1:-2]
print("7:   ",s1)

s = 'hello world hello world Hello world Python'
#find(self, sub, start=None, end=None)
idx = s.find('o')
print(idx)
idx = s.find('o',8 ,20)
print(idx)
#rfind也是一样的参数
idx = s.rfind('o',8 ,20)
print(idx)
#index(self, sub, start=None, end=None)
idx = s.index('o',8 ,20)
print(idx)
#index和find函数的参数一样，但是主要是返回值不一样，find函数找不到字串时会返回-1.index找不到字串时程序会崩溃，产生异常信息，导致程序无法执行
idx = s.index('o',8 ,10)
print(idx)
idx = s.find('o',8 ,10)
print(idx)

s = 'hello world hello world Hello world Python'
#替换replace()
#替换时默认替换所有的符合的字串
print(s.replace('l','P'))
print(s)
print('---------------------------------------------------------------------------------------------')
#替换时替换3个符合的字串
print(s.replace('l','P',3))
print(s)

s = 'hello world hello world Hello world Python'
#count计数，查找字符串在父串出现的次数
print(s.count('o'))
#count计数，查找字符串在父串出现的次数，指定开头和结尾下标
print(s.count('o',1,10))

s = 'hello world hello world Hello world Python'
#split分割字符串
a = s.split(' ')
print(a)
print(type(a))
#split分割字符串
a = s.split('or')
print(a)
print(type(a))
ss = 'hello\tworld hello\t\nworld Hello\nworld\r\nPython'
print(ss)
#splitlines分割字符串 按\r\n或者\n分割
print(ss.splitlines())
print("-----------------------------------------------------------------------------------------------")
#partition分割，按分割条件将字符分割成三部分，分割条件前，分割条件，分割条件后
s = 'hello world hello world Hello world Python'
print(s.partition('ll'))
#rpartition() 从右侧进行分割
print(s.rpartition('ll'))
#join()连接的值是可迭代的，我们这里目前直接出了字符串可迭代的
#结果是每一个元素都被'-'连接了
s = 'hello world hello world Hello world Python'
print('-'.join(s))
print("-------------------------------------------------------------------------")
#join的简单应用
s = 'hello world hello world Hello world Python'
s_s = s.split()
print(s_s)
j_s = '$'.join(s_s)
print(j_s)
#join存在的问题：一个元素是无法连接的
print('$'.join('A'))

#判断是否以指定字符串开头
print('1380013800'.startswith('138'))
print('1830013800'.startswith('138'))
print('1230013800'.startswith('138'))
print('-------------------------------------------------------------------------------------------------------------------')
#判断网址后缀
print('www.xxxgov.com'.endswith('.gov'))
print('www.xxxgov.gov'.endswith('.gov'))
print("----------------------------------------------------------------------------------------------------")
#判断大写
print("hello".isupper())
print("Hello".isupper())
print("HELLO".isupper())
print("----------------------------------------------------------------------------------------------------")
#判断小写
print("hello".islower())
print("Hello".islower())
print("HELLO".islower())
print("----------------------------------------------------------------------------------------------------")
#判断字符串是否为纯字母
print("he22lo".isalpha())
print("He123o".isalpha())
print("HELLO".isalpha())
print("----------------------------------------------------------------------------------------------------")
#判断字符串是否为纯数字
print("1234323".isdigit())
print("He123o".isdigit())
print("HELLO".isdigit())
print("----------------------------------------------------------------------------------------------------")
#判断字符串是否包含数字或字符
print("he2--o".isalnum())
print("He123o".isalnum())
print("123123".isalnum())

s = '|         Hello     world         |'
#去除空格
print(s)
#这里空格没去掉的原因是因为有'|'字符
print(s.strip())
print('_______________________________________________________________________________________________')
s = '         Hello     world         '
#去掉两边的空格
print('|' + s.strip() + '|')
print('|' + s.rstrip() + '|')
print('|' + s.lstrip() + '|')
#去掉空格函数组合方式
print('_______________________________________________________________________________________________')
s = '         Hello     world         '
ret = s.split()
print(ret)
print(''.join(ret))

t1 = ()
print(t1)
print(type(t1))
#定义包含其他数据类型的元组
t3 = ('a','b','hello','world')
print(t3)
#元组嵌套元组
t4 = (1233,'b','hello',True,t3)
print(t4)
print("——————————————————————————————————————————————————————————————————————————————————————————————————————")
#定义具有一个元素的元组，特殊，注意，重点
t5 = (1)
print(t5)
print(type(t5))
t5 = ('1')
print(t5)
print(type(t5))
print("——————————————————————————————————————————————————————————————————————————————————————————————————————")
#使用类型名定义元组
t6 = tuple()
print(t6)
print(type(t6))
#注意元组内要放入可迭代的数据，我这里放的是字符串
t7 = tuple('hello')
print(t7)

t = (1,2,3,4,5,"hello")
#方法1 for in
for v in t:
    print(v)
#方法2 for in range
for i in range(len(t)):
    print(t[i])
#方法3 while
i = 0
while i < len(t):
    print(t[i])
    i += 1
print("——————————————————————————————————————————————————————————————————————————————————————————————————————————————————")
#嵌套元组的遍历
#这里的报错是因为混合元组里面有一个元素，所以变成int类型的元素，是不可以迭代的
t = (1,2,3,(4,5,6),(7,8,9))
for v in t:
    for v2 in v:
        print(v2)

#嵌套元组的遍历
#这里的报错是因为混合元组里面有一个元素，所以变成int类型的元素，是不可以迭代的
t = (1,2,3,(4,5,6),(7,8,9))
for v in t:
    #判断参数1是否是参数2的类型对象
    if isinstance(v,tuple):
        for v2 in v:
            print(v2)
    else:
        print(v)