python代码

• 原始字符串，不做任何特殊的处理

• print("Newlines    are    indicated    by    \n")#Newlines    are    indicated    by    
  print(r"Newlines    are    indicated    by    \n")#Newlines    are    indicated    by    \n

• 格式输出，转化为字符串由format自动完成

• age    =    20 
  name    =    'Swaroop'
  print('{0}    was    {1}    years    old    when    he    wrote    this    book'.format(name,    age))

• 元组字典做函数参数

• def    total(a=5,    *numbers,    **phonebook):                
      print('a',    a)    
      
      for    single_item    in    numbers:                                
          print('single_item',    single_item)
                      
      for    first_part,    second_part    in    phonebook.items():                                
          print(first_part,second_part)
  print(total(10,1,2,3,Jack=1123,John=2231,Inge=1560))

• 字符串连接链表

• delimiter    =    '____' 
  mylist    =    ['Brazil',    'Russia',    'India',    'China'] 
  print(delimiter.join(mylist))#Brazil____Russia____India____China

• 类变量、方法，对象变量、方法

• class Robot:
      '''表示有一个带有名字的机器人。'''
      #类变量
      population = 0
      __population2 = 0#双下划线代表私有
      def __init__(self, name):
      #对象变量
          self.name = name
          self.__name2 = name#双下划线代表私有
          Robot.population += 1
      #对象方法
      def die(self):
          Robot.population -= 1
      #类方法，用classmethod定义
      @classmethod
      def how_many(self):
          print("We have {:d} robots.".format(self.population))
  Robot("蒋凯楠").how_many()

• 代码中有中文导致的错误加入下面的代码，注意别忘了等号

• # coding=gbk

• try--except--else
  try--except--finally

• #coding=gbk
  '''
  try--except--else
  try--except--finally
  else只在没有异常时执行,有异常时不执行else
  finally一定会被执行，无论有没有异常
  except在异常匹配时执行
  '''
  import time
  try:
          for i in range(1, 2, 1):
                  print(i)
                  time.sleep(1)
          raise KeyboardInterrupt()
  except KeyboardInterrupt:
          print("CTRL+C后，except执行了")
  finally:
          print("CTRL+C后，finally执行了")