python学习笔记7-异常处理

1 写弄成了读

1 try:
2    fh = open("testfile", "r")
3    fh.write("This is my test file for exception handling!!")
4 except IOError:
5    print ("Error: can\‘t find file or read data")
6 
7 else:
8    print ("Written content in the file successfully")
9 Error: can‘t find file or read data

1 #异常触发
2 def functionName( level ):
3    if level < 1:
4       raise "Invalid level!", level
5       # The code below to this would not be executed
6       # if we raise the exception

1 #自定义异常
2 class Networkerror(RuntimeError):
3    def __init__(self, arg):
4       self.args = arg
5 
6 try:
7    raise Networkerror("Bad hostname")
8 except Networkerror,e:
9    print e.args