四、string操作

• 连接字符串

s1 = "hello"
s2 = " world"
s = s1 + s2
print(s)

#中间插入一个元素
string = "1234567"

newstr = string[:3] + "a" + string[3:]
print(newstr)

显示结果
123a4567

• 截取字符串

string = "hello world"
print(string)
sub = string[0:3]
print(sub)

• 替换字符

string = "hello world"
s = string.replace("e", "a")
print(s)
print(string)

• 包含 查找

s1 = "abcdef"
s2 = "bcd"

print(s2 in s1)
print(s1.find(s2))

• 大写、小写

string = "Hello World"
# 小写
print(string.lower())
# 大写
print(string.upper())
# 开头字母大写
print(string.capitalize())
print(string)

• 以...开头

s1 = "abcdef"
isstart = s1.startswith("abc")
print(isstart)
isend = s1.endswith("ef")
print(isend)

• 编码转换

# 网页读出的数据 会出现乱码 或unicode编码
s = str(html, "utf-8")
print(s)