python自定义异常

try             异常在try块里抛,如果会产生多个异常,捕捉第一个,匹配except,后边的不再捕捉

except: 抓异常

else:       try无异常,才会执行else

finally:   无论try块是否抛异常,永远执行的代码,通常用来执行关闭文件,断开服务器连接的功能

[root@133 systeminformation]# vim ErrorExcept.py#!/usr/bin/env python                                                                                                                                                              #ecoding:utf-8                                                                                                                                                                                                                                                                                                                                                        class FuncError(Exception):                                                                                                                                                            def __str__(self):                                                                                                                                                                     return "I am func Error"                                                                                                                                                                                                                                                                                                                                      def fun():                                                                                                                                                                             raise FuncError() #raise 抛出异常"I am func Error"                                                                                                                                                                                                                                                                                                                try:                                                                                                                                                                                   fun()                                                                                                                                                                          except FuncError,e:                                                                                                                                                                    print e                                                                                                                                                                                                                                                                                                                                                           print 'hello world'   [root@133 systeminformation]# python ErrorExcept.py I am func Errorhello world

#!/usr/bin/env python                                                                                                                                                              #ecoding:utf-8                                                                                                                                                                     class FuncError(Exception):    def __str__(self):        return "I am func Error"def fun():    raise FuncError() #raise 抛出异常"I am func Error"try:   #fun()                                                                                                                                                               print  'a'         #print 'a'正确显示结果,如果是print a,报错name error,打印!!                                                                                                                                           except FuncError,e:    #如果print a 和fun()同时存在,print a在前,会打印!!,不打印I am fun error, fun()在前,打印I am fun error,不打印!!                                                                                                                                            print e                                                                                                                                                       except NameError:                                                                                                                                                     print '!!'                                                                                                                                                   else:                  #不抛异常,输出a,这种情况下执行else内容                                                                                                                                             print 'else'                                                                                                                                                  finally:               #finally无论如何都执行                                                                                                                                             print 'finally'print 'hello world'    #print一定会执行[root@133 systeminformation]# python ErrorExcept.py                                                                                                                                aelsefinallyhello world#!/usr/bin/env python                                                                                                                                                              #ecoding:utf-8                                                                                                                                                                                                                                                                                                                                                        class FuncError(Exception):                                                                                                                                                            def __str__(self):                                                                                                                                                                     return "I am func Error"                                                                                                                                                                                                                                                                                                                                      def fun():                                                                                                                                                                             raise FuncError() #raise 抛出异常"I am func Error"                                                                                                                                                                                                                                                                                                                try:                                                                                                                                                                                  fun()               #即使有两个异常,抛出一个异常I am func Error,不再抛出第二个                                                                                                                                                                      print  a                                                                                                                                                                  except Exception:       #匹配所有异常,匹配即结束,打印all exception                                                                                                                                                              print 'all exception'                                                                                                                                                          except FuncError,e:                                                                                                                                                                    print e                                                                                                                                                                        except NameError:                                                                                                                                                                      print '!!'                                                                                                                                                                     else:                   #没有异常菜执行else,有异常不执行                                                                                                                                                           print 'else'                                                                                                                                                                   finally:                                                                                                                                                                               print 'finally'                                                                                                                                                                print 'hello world'  [root@133 systeminformation]# python ErrorExcept.py all exceptionfinallyhello world

glob:python下类似shell中的*的通配符

In [1]: import glob                                                                                                                                                                                                                                                                                                                                                   In [2]: glob.glob('/etc/*.conf')    #匹配/etc下*.conf文件,保存到list中                                                                                                                                              Out[2]:                                                                                                                                                                            ['/etc/rsyslog.conf', '/etc/sensors3.conf', '/etc/GeoIP.conf', '/etc/Trolltech.conf', '/etc/nfsmount.conf',

shlex :分词模块,

[root@133 ~]# ps -eo pid,ppid,cmd                                                                                                                                              PID  PPID CMD    1     0 /sbin/init    2     0 [kthreadd]    3     2 [migration/0]    4     2 [ksoftirqd/0][root@133 ~]# ipythonIn [1]: import shlex                                                                                                                                                                                                                                                                                                                                                  In [2]: cmd = "ps -eo pid,ppid,cmd"                                                                                                                                                                                                                                                                                                                                   In [3]: shlex.split(cmd)              #返回列表元素                                                                                                                                              Out[3]: ['ps', '-eo', 'pid,ppid,cmd']                                                                                                                                              In [4]: import subprocess                                                                                                                                                                                                                                                                                                                                             In [5]: subprocess.check_call(shlex.split(cmd))                                                                                                                                      PID  PPID CMD                                                                                                                                                                        1     0 /sbin/init                                                                                                                                                                 2     0 [kthreadd]                                                                                                                                                                 3     2 [migration/0]