字符串的操作及其部分格式化

#字符串的操作及其部分格式化
i=3
str="FGdV"
while i>0:
    i=i-1
    user_input=input("please enter security code:")
    if str.upper()==user_input.upper():
           print("Input success")
           break
    else:
           print("please enter again:")

    print("You have %d more chances" %(i))
print("Game over")

#这个方法是让验证码与用户输入都变成大写来匹配，如果验证时就是
#大写的匹配大写的，小写的匹配小写的又该怎么做呢,字母的大小写的操作对数字是没影响的哦



#字符串的操作
#capitalize 使字符串的首字母大写
a="hello LInda"
b=a.capitalize()#Hello linda 会把原来字符串中的大写的变为小写
print(b)


b1=a.upper()
print(b1)#HELLO LINDA upper 把字符串全部变为大写

b2=a.lower()#hello linda 把字符串全变为小写
print(b2)

#字符串的用途：验证码 不区分大小写，你怎样判断验证码正确
i=3
while i>0:
    i=i-1
    str="hvhGH"
    user_input=input("please enter security code：")
    if str.upper()==user_input.upper():
        print("login successfully")
        break
    else:
        print("please enter again")
        print("you only have %d chance" %(i))
print("Your chance is up")

#把原来的验证码与用户输入的验证码都转换成一个标准，让用户最多可输入三次


b3=a.swapcase()#把字符串中大写的变为小写，小写的边为大写
print(b3)#HELLO liNDA swapcase 

'''

'''
b="you are the timeless memony in my heart"
b1=b.title()#把字符串的首字母变为大写 
print(b1)#You Are The Timeless Memony In My Heart title


c="you are the6timeless memony in my56heart"
b2=c.title()
print(b2)

c1="you are the6timeless me#mony in my56he$art"
b3=c1.title()# 当然title也会把用特殊字符或数字隔开的单词首字母大写
print(b3)#You Are The6Timeless Me#Mony In My56He$Art 

b="you are the timeless memony in my heart"
b1=b.center(80)#center(可填数字）用于使str居中，此例就是使str位于80个位的中间
print(b1)#                    you are the timeless memony in my heart  


a="helloworld hello"
a1=a.startswith("he")#用于判断字符串是否以括号里的字符开始
print(a1)#true 结果

a2=a.startswith("l",3,6)#判断字符l是否在位置为2且到5的字符串中
print(a2)

'''
'''
a="helloworld hello"
a3=a.find("w")
a4=a.find("k")
print(a3)#5
print(a4)#-1
#find 找到字符，返回该字符的索引，找不到则返回-1
a5=a.find("wo")
a6=a.find("gh")
print(a5)#5
print(a6)#-1
#如果是寻找多个字符，则返回第一个字符所在的索引，若没有查找到则返回-1

a7=a.index("l")
#a8=a.index("m")
print(a7)#返回字符的索引，查找不到就报错
#print(a8)


name=input("please enter your name:").strip()
if name=="Linda":
    print("Hello Linda")
else:
    print("name is error")

#加了strip就算再输入姓名时，误输入了空格也不会出错，strip默认删除前后空格
#lstrip()删除左边的空格，rstrip()删除右边的空格


d="IloveChina I love china LOVE"
d1=d.count("o")#数出字符串中的字母o有多少个
print(d1)#2

d2=d.split("o")#按照你所写的拆分规则，把字符串拆分为列表
d3=d.split(" ")#被分割的元素就不存在了
print(d2)#['Il', 'veChina I l', 've china LOVE']
print(d3)#['IloveChina', 'I', 'love', 'china', 'LOVE']

'''
'''
s="I am {},age is {},I am {}".format("Linda",18,"Linda")
print(s)                                      

s1="I am {0},age is {1},I am {0}".format("Linda",18)
print(s1)

s2="I am {name},age is {age},I am {name}".format(name="Linda",age=18)
print(s2)
s3=s.replace("Linda","Chichy")#把Linda替换成Chichy
s4=s.replace("Linda","Chichy",1)#有数字1就只替换一次
print(s3)
print(s4)





I am Linda,age is 18,I am Linda
I am Linda,age is 18,I am Linda
I am Linda,age is 18,I am Linda
I am Chichy,age is 18,I am Chichy
I am Chichy,age is 18,I am Linda

f="Hello Linda,Welcome to China"
if "Linda" in f:
    print("Welcome to China")
else:
    print("Linda not exist")
#Welcome to China

'''