介绍

当 Python 检测到一个错误时，解释器就无法继续执行了。反而会出现一些错误的提示，这就是所谓的异常。

例如这里，打开一个不存在的文件，就会报异常了。

f = open("python.txt", "r", encoding="utf-8")

Traceback (most recent call last):
  File "/Users/aaron/Desktop/py/hello.py", line 1, in <module>
    f = open('python.txt', 'r', encoding='utf-8')
FileNotFoundError: [Errno 2] No such file or directory: 'python.txt'

Process finished with exit code 1

捕获异常

try:
    open("python.txt")
except IOError:
    prin...