字符串的内置方法

类型对象,该类型对象拥有的方法

点击查看代码

s = "Hello world"
s2 = "rain"
# new_s1 = s1.upper()
# new_s2 = s2.upper()
print(s1.upper())  # 字符串改为大写
print(s1.lower())  # 字符串改为小写

print(s1.startswith("H"))  # 判断以什么开头
print(s1.startswith("He"))    # True
print(s1.startswith("Hel"))   # True
print(s1.startswith("World")) # False
print(s1.startswith("ell"))  # False
print(s1.startswith("h"))  # False

print(s1.endswith("World"))  #判断以什么结尾 True
print(s1.endswith("ld"))  # True

print(s1.replace("World","Yuan")) # 替换 Hello Yuan
print(s1)` # Hello World

num = "100" # 数字字符串
print(num.isdigit)
word = " Hello world    "
print(word)
print(len(world)) # 计算某一个序列类型的长度,有多少元素,字符

print(word.strip()) # 去掉两边的空格

# 最重要的两个方法: split(分割) join(拼接)
s = "北京,上海,深圳,广州"
cities = s.split(",") # ["北京","上海","深圳","广州"]
print(cities)
print(cities[1])
print(cities[3])
print(len(cities))

print(",".join(cities)) # "北京,上海,深圳,广州"   是以","的方法拼接成字符串

# index()方法:查索引
s1 = "Hello world"
print(s1.index("W"))
print(s1.index("o"))
print(s1.index("World"))