①所有字母都转换为大写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'hello, world!'
print(a.upper())输出：
HELLO, WORLD!
②所有字母都转换为小写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'HELLO, WORLD!'
print(a.lower())输出：
hello, world!
③首字母转换成大写， 其余转换成小写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'HELLO, WORLD!'
print(a.capitalize())输出：
Hello, world!
④所有单词的首字母转换成大写， 其余转换成小写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'HELLO, WORLD!'
print(a.title())输出：
Hello, World!
⑤判断所有字母都为大写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'HELLO, WORLD!'
print(a.isupper())
b = 'hello, world!'
print(b.isupper())输出：
True
False
⑥判断所有字母都为小写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'HELLO, WORLD!'
print(a.islower())
b = 'hello, world!'
print(b.islower())输出：
False
True
⑦判断所有单词的首字母为大写
# -*- coding:utf-8 -*-
if __name__ == "__main__":
a = 'HELLO, WORLD!'
print(a.istitle())
b = 'hello, world!'
print(b.istitle())
c = 'Hello, World!'
print(c.istitle())输出：
False
False
True
以上这篇Python 字符串大小写转换的简单实例就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。