常见的异常：

 

处理单个异常

#!/usr/bin/env Python# coding=utf-8class Calculator(object):    is_raise = False    def calc(self, express):        try:            return eval(express)        except ZeroDivisionError:            if self.is_raise:                print "zero can not be division."            else:                raise　　　　　　　　　　　　　　　　#作为单独一个语句。它的含义是将异常信息抛出if __name__ == "__main__":    c = Calculator()    c.is_raise = True    print c.calc("8/0")

运行结果：

 

处理多个异常

#!/usr/bin/env Python# coding=utf-8while 1:    print "this is a division program."    c = raw_input("input 'c' continue, otherwise logout:")    if c == 'c':        a = raw_input("first number:")        b = raw_input("second number:")        try:            print float(a)/float(b)            print "*************************"        except ZeroDivisionError:            print "The second number can't be zero!"            print "*************************"        except ValueError:            print "please input number."            print "************************"    else:        break

可以加一个else语句

#!/usr/bin/env Python# coding=utf-8while 1:    try:        x = raw_input("the first number:")        y = raw_input("the second number:")        r = float(x)/float(y)        print r    except Exception, e:        print e        print "try again."    else:        break

这样执行如果没有异常就退出

也可以在最后添加一个finally语句，综合起来异常表达式：

try:    do somethingexcept:    do somethingelse:    do somethingfinally    do something