1 # coding=utf-82 3 print "你好，世界。"

1 print 2**10

1 var = 12 print var3 4 var  = "段光伟"5 print var

1 #获取用户输入2 x = input("x:")3 y = input("y:")4 5 print x*y

1 def say_b():2     print "b"

1 #1 + “1” 这行代码在Python中会报错。2 print 1 + int("1")3 print str(1) + "1"

1 #字符串2 print ‘‘‘‘    段3             光4             伟‘‘‘5 print r‘C:\log.txt‘6 print ‘C:\\log.txt‘

 1 seq = "0123456789" 2 print seq[0] #从0开始编码。 3 print seq[-1] #支持倒着数数，-1代表倒数第一。 4 print seq[1:5] #支持分片操作，seq[start:end]，start会包含在结果中，end不会包含在结果中。 5 print seq[7:] #seq[start:end]中的end可以省略。 6 print seq[-3:] #分片也支持负数。 7 print seq[:3] #seq[start:end]中的start也可以省略。 8 print seq[:] #全部省略会复制整个序列。 9 print seq[::2] #支持步长。10 print seq[::-2] #支持负步长。11 print seq[9:1:-1] #支持负步长。12 print [1, 2, 3] + [4, 5, 6] # 序列支持相加，这解释了为啥字符串可以相加。13 print [1, 2, 3] * 3 #序列支持相乘，这解释了为啥字符串可以相称。14 print [None] * 10 #生成一个空序列。15 print 1 in [1, 2, 3] #成员判断。

 1 data = http://www.mamicode.com/[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];"a" #修改元素。 4 print data 5 data[0] = 0 6  7 del data[10] #删除元素。 8 print data 9 10 del data[8:] #分片删除。11 print data12 13 data[8:] = [8, 9, 10] #分片赋值14 print data

1 print (1, 2) #元祖以小括号形式声明。2 print (1,) #一个元素的元祖。

1 print "% 10s" % "----"2 3 print ‘‘‘4 %(title)s5 %(body)s6 ‘‘‘ % {"title": "标题", "body": "内容"}

1 print {"title": "title", "body": "body"}2 print dict(title = "title", body = "body")3 print dict([("title", "title"), ("body", "body")])

1 dic = {"title": "title", "body": "body"};2 print dic["title"]3 del dic["title"]4 print dic

1 print ‘a‘, ‘b‘ #print可以接受多个参数，参数的输出之间以空格相隔。2 print ‘a‘, #如果逗号之后没有参数，则不会换行。3 print ‘b‘

1 x, y, z = 1, 2, 32 print x, y, z3 (x, y, z) = (1, 2, 3)4 print x, y, z5 (x, y, z) = [1, 2, 3]6 print x, y, z

 1 #下面的输入全部返回False。 2 print(bool(None)) 3 print(bool(())) 4 print(bool([])) 5 print(bool({})) 6 print(bool("")) 7 print(bool(0)) 8  9 #虽然这些值在条件运算中会当做False，但是本身不等于False。10 print(True and "")11 print(not "")12 print(False == "")13 print(False == 0) #0除外，bool类型的内部表示就是int类型。

1 print(0 < 1 < 10)2 print(0 < 1 and 1 < 10)3 print(not(0 > 1 > 10))4 print(not(0 > 1 or 1 > 10))

1 if(10 > 1):2     print("10 > 1")3 else:4     print("不可能发生")

1 print("10 > 1" if 10 > 1 else "不可能发生")

1 #== 和 is的差别，==比较的是内容，is比较的是引用。2 x = [1, 2, 3]3 y = x4 z = [1, 2, 3]5 print(x == y)6 print(x == z)7 print(x is y)8 print(x is z)

 1 #for循环类似C#的foreach，注意for后面是没有括号的，python真是能简洁就尽量简洁。 2 for x in range(1, 10): 3     print(x) 4  5 for key in {"x":"xxx"}: 6     print(key) 7  8 for key, value in {"x":"xxx"}.items(): 9     print(key, value)10 11 for x, y, z in [["a", 1, "A"],["b", 2, "B"]]:12     print(x, y, z)

 1 #带索引的遍历 2 for index, value in enumerate(range(0, 10)): 3     print(index, value) 4  5 #好用的zip方法 6 for x, y in zip(range(1, 10), range(1, 10)): 7     print(x, y) 8  9 #循环中的的else子句10 from math import sqrt11 for item in range(99, 1, -1):12     root = sqrt(item)13     if(root == int(root)):14         print(item)15         break16 else:17     print("没有执行break语句。")

1 #pass、exec、eval2 if(1 == 1):3     pass4 5 exec(‘print(x)‘, {"x": "abc"})6 print(eval(‘x*2‘, {"x": 5}))

 1 # 基本函数定义。 2 def func(): 3     print("func") 4  5 func() 6  7 # 带返回值的函数。 8 def func_with_return(): 9     return ("func_with_return")10 11 print(func_with_return())12 13 # 带多个返回值的函数。14 def func_with_muti_return():15     return ("func_with_muti_return", "func_with_muti_return")16 17 print(func_with_muti_return())18 19 # 位置参数20 def func_with_parameters(x, y):21     print(x, y)22 23 func_with_parameters(1, 2)24 25 # 收集多余的位置参数26 def func_with_collection_rest_parameters(x, y, *rest):27     print(x, y)28     print(rest)29 30 func_with_collection_rest_parameters(1, 2, 3, 4, 5)31 32 #命名参数33 def func_with_named_parameters(x, y, z):34     print(x, y, z)35 36 func_with_named_parameters(z = 1, y = 2, x = 3)37 38 #默认值参数39 def func_with_default_value_parameters(x, y, z = 3):40     print(x, y, z)41 42 func_with_default_value_parameters(y = 2, x = 1)43 44 #收集命名参数45 def func_with_collection_rest_naned_parameters(*args, **named_agrs):46     print(args)47     print(named_agrs)48 49 func_with_collection_rest_naned_parameters(1, 2, 3, x = 4, y = 5, z = 6)50 51 #集合扁平化52 func_with_collection_rest_naned_parameters([1, 2, 3], {"x": 4, "y": 4, "z": 6}) #这会导致args[0]指向第一个实参，args[1]指向第二个实参。53 func_with_collection_rest_naned_parameters(*[1, 2, 3], **{"x": 4, "y": 4, "z": 6}) #这里的执行相当于func_with_collection_rest_naned_parameters(1, 2, 3, x = 4, y = 5, z = 6)。

 1 # coding=utf-8 2  3 # 只有函数执行才会开启一个作用域。 4 if(2 > 1): 5     x = 1 6  7 print(x) # 会输出1。 8  9 10 # 使用vars()函数可以访问当前作用域包含的变量。11 x = 112 print(vars()["x"])13 14 # 使用globals()函数可以访问全局作用域。15 x = 116 17 def func():18     print(globals()["x"])19 20 func()21 22 # 使用locals()函数可以访问局部作用域。23 def func():24     x = 225     print(locals()["x"])26 27 func()28 29 # 每个函数定义时都会记住所在的作用域。30 # 函数执行的时候会开启一个新的作用域，函数内变量访问的规则是：先访问当前作用域，如果没有就访问函数定义时的作用域，递归直到全局作用域。31 x = 132 33 def func():34     y = 235     print(x, y) # 输出1 236 37 func()38 39 40 # 变量赋值始终访问的是当前作用域。41 x = 142 43 def func():44     x = 245     y = 246     print(x, y) # 输出2 247 48 func()49 print(x) #输出 150 51 # 局部变量会覆盖隐藏全局变量，想访问全局变量可以采用global关键字或globals()函数。52 x = 153 54 def func():55     global x56     x = 257     y = 258     print(x, y) # 输出2 259 60 func()61 print(x) #输出 2

 1 # python支持闭包 2 def func(x): 3     def inner_func(y): 4         print(x + y) 5  6     return inner_func 7  8 inner_func = func(10) 9 inner_func(1)10 inner_func(2)

1 #函数作为对象2 def func(fn, arg):3     fn(arg)4 5 func(print, "hello")6 func(lambda arg : print(arg), "hello")

1 # coding=utf-82 3 print __name__4 5 def say_b():6     print "b"

1 # coding=utf-82 3 import b4 from b import *5 6 print __name__7 8 def say_a():9     print "a"

1 # coding=utf-82 3 import a4 5 print __name__6 7 a.say_a();8 a.say_b();9 a.b.say_b()

1 b2 a3 __main__4 a5 b6 b

 1 # coding=utf-8 2  3 # 自定义异常 4 class HappyException(Exception): 5     pass 6  7 # 引发和捕获异常 8 try: 9     raise HappyException10 except:11     print("HappyException")12 13 try:14     raise HappyException()15 except:16     print("HappyException")17 18 # 捕获多种异常19 try:20     raise HappyException21 except (HappyException, TypeError):22     print("HappyException")23 24 # 重新引发异常25 try:26     try:27         raise HappyException28     except (HappyException, TypeError):29         raise30 except:31     print("HappyException")32 33 #访问异常实例34 try:35     raise HappyException("都是我的错")36 except (HappyException, TypeError), e:37     print(e)38 39 #按类型捕获40 try:41     raise HappyException42 except HappyException:43     print("HappyException")44 except TypeError:45     print("TypeError")46 47 #全面捕获48 try:49     raise HappyException50 except:51     print("HappyException")52 53 #没有异常的else54 try:55     pass56 except:57     print("HappyException")58 else:59     print("没有异常")60 61 #总会执行的final62 try:63     pass64 except:65     print("HappyException")66 else:67     print("没有异常")68 finally:69     print("总会执行")

 1 # coding=utf-8 2  3 __metaclass__ = type 4  5 # 类型定义 6 # 实例方法必的第一个参数代表类型实例，类似其他语言的this。 7 class Animal: 8     name = "未知" # 属性定义。 9 10     def __init__(self, name): #构造方法定义。11         self.name = name12 13     def getName(self): # 实例方法定义。14         return self.name15 16     def setName(self, value):17         self.name = value18 19 print(Animal.name) # 未知20 print(Animal.__dict__["name"]) # 未知21 22 animal = Animal("狗狗")23 print(animal.name) # 狗狗24 print(animal.__dict__["name"]) # 狗狗25 print(Animal.name) # 未知26 print(Animal.__dict__["name"]) # 未知27 print(animal.__class__.name) # 未知28 print(animal.__class__.__dict__["name"]) # 未知

1 # 类型定义中的代码会执行，是一个独立的作用域。2 class TestClass:3     print("类型定义中") #类型定义中

 1 class TestClass: 2     def method(self): 3         print("测试方法") 4  5 test = TestClass() 6 print(TestClass.method) #<unbound method TestClass.method> 7 print(test.method) #<bound method TestClass.method of <__main__.TestClass object at 0x021B46D0>> 8  9 TestClass.method(test) #测试方法10 test.method() #测试方法

1 # 私有成员2 class TestClass:3     __private_property = 14 5     def __private_method():6         pass7 8 print(TestClass.__dict__) # {‘__module__‘: ‘__main__‘, ‘_TestClass__private_method‘: <function __private_method at 0x0212B970>, ‘_TestClass__private_property‘: 1

 1 #多重继承 2 class Base1: 3     pass 4  5 class Base2: 6     pass 7  8 class Child(Base2, Base1): 9     pass10 11 child = Child()12 print(isinstance(child, Child)) # True13 print(isinstance(child, Base2)) # True14 print(isinstance(child, Base1)) # True

 1 class TestClass1: 2     def say(self): 3         print("我是鸭子1") 4  5 class TestClass2: 6     def say(self): 7         print("我是鸭子2") 8  9 def duck_say(duck):10     duck.say()11 12 duck_say(TestClass1()) # 我是鸭子113 duck_say(TestClass2()) # 我是鸭子2

 1 # 调用父类 2 class Base: 3     def say(self): 4         print("Base") 5  6 class Child(Base): 7     def say(self): 8         Base.say(self) 9         super(Child, self).say()10         print("Child")11 12 child = Child()13 child.say()

 1 from os.path import join 2  3 class FileObject: 4     ‘‘‘Wrapper for file objects to make sure the file gets closed on deletion.‘‘‘ 5  6     def __init__(self, filepath=‘~‘, filename=‘sample.txt‘): 7         # open a file filename in filepath in read and write mode 8         self.file = open(join(filepath, filename), ‘r+‘) 9 10     def __del__(self):11         self.file.close()12         del self.file

 1 class Word(str): 2     ‘‘‘Class for words, defining comparison based on word length.‘‘‘ 3  4     def __new__(cls, word): 5         # Note that we have to use __new__. This is because str is an immutable 6         # type, so we have to initialize it early (at creation) 7         if ‘ ‘ in word: 8             print "Value contains spaces. Truncating to first space." 9             word = word[:word.index(‘ ‘)] # Word is now all chars before first space10         return str.__new__(cls, word)11 12     def __gt__(self, other):13         return len(self) > len(other)14 15     def __lt__(self, other):16         return len(self) < len(other)17 18     def __ge__(self, other):19         return len(self) >= len(other)20 21     def __le__(self, other):22         return len(self) <= len(other)23 24 print(Word("duan") > Word("wei"))

 1 class AccessCounter: 2     ‘‘‘A class that contains a value and implements an access counter. 3     The counter increments each time the value is changed.‘‘‘ 4  5     def __init__(self, value): 6         super(AccessCounter, self).__setattr__(‘counter‘, 0) 7         super(AccessCounter, self).__setattr__(‘value‘, value) 8  9     def __setattr__(self, name, value):10         if name == ‘value‘:11             super(AccessCounter, self).__setattr__(‘counter‘, self.counter + 1)12         # Make this unconditional.13         # If you want to prevent other attributes to be set, raise AttributeError(name)14         super(AccessCounter, self).__setattr__(name, value)15 16     def __delattr__(self, name):17         if name == ‘value‘:18             super(AccessCounter, self).__setattr__(‘counter‘, self.counter + 1)19         super(AccessCounter, self).__delattr__(name)

 1 class FunctionalList: 2     ‘‘‘A class wrapping a list with some extra functional magic, like head, 3     tail, init, last, drop, and take.‘‘‘ 4  5     def __init__(self, values=None): 6         if values is None: 7             self.values = [] 8         else: 9             self.values = values10 11     def __len__(self):12         return len(self.values)13 14     def __getitem__(self, key):15         # if key is of invalid type or value, the list values will raise the error16         return self.values[key]17 18     def __setitem__(self, key, value):19         self.values[key] = value20 21     def __delitem__(self, key):22         del self.values[key]23 24     def __iter__(self):25         return iter(self.values)26 27     def __reversed__(self):28         return FunctionalList(reversed(self.values))29 30     def append(self, value):31         self.values.append(value)32     def head(self):33         # get the first element34         return self.values[0]35     def tail(self):36         # get all elements after the first37         return self.values[1:]38     def init(self):39         # get elements up to the last40         return self.values[:-1]41     def last(self):42         # get last element43         return self.values[-1]44     def drop(self, n):45         # get all elements except first n46         return self.values[n:]47     def take(self, n):48         # get first n elements49         return self.values[:n]

 1 class Entity: 2     ‘‘‘Class to represent an entity. Callable to update the entity‘s position.‘‘‘ 3  4     def __init__(self, size, x, y): 5         self.x, self.y = x, y 6         self.size = size 7  8     def __call__(self, x, y): 9         ‘‘‘Change the position of the entity.‘‘‘10         self.x, self.y = x, y11         print(x, y)12 13 entity = Entity(5, 1, 1)14 entity(2, 2)

 1 class Closer: 2     def __enter__(self): 3         return self 4  5     def __exit__(self, exception_type, exception_val, trace): 6         print("清理完成") 7         return True; 8  9 with Closer() as closer:10     pass

 1 class Meter(object): 2     ‘‘‘Descriptor for a meter.‘‘‘ 3  4     def __init__(self, value=http://www.mamicode.com/0.0):>

1 # coding=utf-82 3 def paly(self):4     print("游戏中...")

1 # coding=utf-82 3 class Animal:4     from playable import paly5 6 animal = Animal()7 animal.paly() # 游戏中...

 1 #coding:utf-8 2  3 class TestClass: 4     def method1(self): 5         print("方法1") 6  7 def method2(self): 8     print("方法2") 9 10 TestClass.method2 = method211 12 test = TestClass()13 test.method1() # 方法114 test.method2() # 方法2

1 TestClass = type("TestClass", (object,), {2     "say": lambda self : print("你好啊")3 })4 5 test = TestClass()6 test.say()

 1 def getter(name): 2     def getterMethod(self): 3         return self.__getattribute__(name) 4     return getterMethod 5  6 def setter(name): 7     def setterMethod(self, value): 8         self.__setattr__(name, value) 9     return setterMethod    10 11 class TestClass:12     getName = getter("name")13     setName = setter("name")14 15 test = TestClass()16 test.setName("段光伟")17 print(test.getName())