从Zero到Hero,一文掌握Python关键代码

 1 #int  2 one=1  3 some_number=100  4  5 print("one=",one) #print type1  6 print("some_number=",some_number) #python3 print need add ()  7  8 """output  9 one= 1 10 some_number= 100 11 """

 1 #booleans  2 true_boolean=True  3 false_boolean=False  4  5 print("true_boolean:",true_boolean)  6 print("False_boolean;",false_boolean)  7  8 """output  9 true_boolean: True 10 False_boolean; False 11 """

1 #string 2 my_name="leizeling" 3 4 print("my_name:{}".format(my_name)) #print type2 5 6 """output 7 true_boolean: True 8 False_boolean; False 9 """

#float book_price=15.80 print("book_price:{}".format(book_price)) """output book_price:15.8 """

 1 #if  2 if True:  3 print("Hollo Python if")  4 if 2>1:  5 print("2 is greater than 1")  6  7 """output  8 Hollo Python if  9 2 is greater than 1 10 """

 1 #if……else  2 if 1>2:  3 print("1 is greater than 2")  4 else:  5 print("1 is not greater than 2")  6  7 """output  8 true_boolean: True  9 False_boolean; False 10 """

#if……elif……else if 1>2: print("1 is greater than 2") elif 1<2: print("1 is not greater than 2") else: print("1 is equal to 2") """output 1 is not greater than 2 """

#while num=1 while num<=10: print(num) num+=1 """output 1 2 3 4 5 6 7 8 9 10 """

 1 #for  2 for i in range(1,11):#range(start,end,step),not including end  3 print(i)  4  5 """output  6 1  7 2  8 3  9 4 10 5 11 6 12 7 13 8 14 9 15 10 16 """

#create integers list my_integers=[1,2,3,4,5] print(my_integers[0]) print(my_integers[1]) print(my_integers[4]) """output 1 2 5 """

#create str list relatives_name=["Toshiaki","Juliana","Yuji","Bruno","Kaio"] print(relatives_name) """output ['Toshiaki', 'Juliana', 'Yuji', 'Bruno', 'Kaio'] """

 1 #add item to list  2 bookshelf=[]  3 bookshelf.append("The Effective Engineer")  4 bookshelf.append("The 4 Hour Work Week")  5 print(bookshelf[0])  6 print(bookshelf[1])  7  8 """output  9 The Effective Engineer 10 The 4 Hour Work Week 11 """

#dictionary struct dictionary_example={"key1":"value1","key2":"value2","key3":"value3"} dictionary_example """output {'key1': 'value1', 'key2': 'value2', 'key3': 'value3'} """

#create dictionary dictionary_tk={"name":"Leandro","nickname":"Tk","nationality":"Brazilian"} print("My name is %s"%(dictionary_tk["name"])) print("But you can call me %s"%(dictionary_tk["nickname"])) print("And by the waay I am {}".format(dictionary_tk["nationality"])) """output My name is Leandro But you can call me Tk And by the waay I am Brazilian """

1 #dictionary add item 2 dictionary_tk["age"]=24 3 print(dictionary_tk) 4 5 """output 6 {'nationality': 'Brazilian', 'nickname': 'Tk', 'name': 'Leandro', 'age': 24} 7 """

#dictionayr del item dictionary_tk.pop("age") print(dictionary_tk) """output {'nationality': 'Brazilian', 'nickname': 'Tk', 'name': 'Leandro'} """

#iteration of list bookshelf=["The Effective Engineer","The 4 hours work week","Zero to One","Lean Startup","Hooked"] for book in bookshelf: print(book) """output The Effective Engineer The 4 hours work week Zero to One Lean Startup Hooked """

 1 #哈希数据结构（iteration of dictionary）  2 dictionary_tk={"name":"Leandro","nickname":"Tk","nationality":"Brazilian"}  3 for key in dictionary_tk: #the attribute can use any name,not only use "key"  4 print("%s:%s"%(key,dictionary_tk[key]))  5 print("===================")  6 for key,val in dictionary_tk.items(): #attention:this is use dictionary_tk.items().not direct use dictionary_tk  7 print("{}:{}".format(key,val))  8  9 """output 10 nationality:Brazilian 11 nickname:Tk 12 name:Leandro 13 =================== 14 nationality:Brazilian 15 nickname:Tk 16 name:Leandro 17 """

#define class class Vechicle: pass

#create instance car=Vechicle() print(car) ""output <__main__.Vechicle object at 0x000000E3014EED30> """

#define class class Vechicle(object):#object is a base class def __init__(self,number_of_wheels,type_of_tank,seating_capacity,maximum_velocity): self.number_of_wheels=number_of_wheels self.type_of_tank=type_of_tank self.seating_capacity=seating_capacity self.maximum_velocity=maximum_velocity def get_number_of_wheels(self): return self.number_of_wheels def set_number_of_wheels(self,number): self.number_of_wheels=number #create instance(object) tesla_models_s=Vechicle(4,"electric",5,250) tesla_models_s.set_number_of_wheels(8)#方法的调用显得复杂 tesla_models_s.get_number_of_wheels() """output 8 """

#use @property让方法像属性一样使用 #define class class Vechicle_1(object):#object is a base class def __init__(self,number_of_wheels,type_of_tank,seating_capacity,maximum_velocity):#first attr must is self,do not input the attr self._number_of_wheels=number_of_wheels ###属性名和方法名不要重复 self.type_of_tank=type_of_tank self.seating_capacity=seating_capacity self.maximum_velocity=maximum_velocity @property #读属性 def number_of_wheels(self): return self._number_of_wheels @number_of_wheels.setter #写属性 def number_of_wheels(self,number): self._number_of_wheels=number def make_noise(self): print("VRUUUUUUUM") tesla_models_s_1=Vechicle_1(4,"electric",5,250) print(tesla_models_s_1.number_of_wheels) tesla_models_s_1.number_of_wheels=2 print(tesla_models_s_1.number_of_wheels) print(tesla_models_s_1.make_noise()) """output 4 2 VRUUUUUUUM None """

 1 #公开实例变量  2 class Person:  3 def __init__(self,first_name):  4 self.first_name=first_name  5 tk=Person("TK")  6 print(tk.first_name)  7 tk.first_name="Kaio"  8 print(tk.first_name)  9 10 """output 11 TK 12 Kaio 13 """

#私有实例变量 class Person: def __init__(self,first_name,email): self.first_name=first_name self._email=email def get_email(self): return self._email def update_email(self,email): self._email=email tk=Person("TK","tk@mail.com") tk.update_email("new_tk@mail.com") print(tk.get_email()) """output new_tk@mail.com """

#公有方法 class Person: def __init__(self,first_name,age): self.first_name=first_name self._age=age def show_age(self): return self._age tk=Person("TK",24) print(tk.show_age()) """output 24 """

 1 #私有方法  2 class Person:  3 def __init__(self,first_name,age):  4 self.first_name=first_name  5 self._age=age  6 def _show_age(self):  7 return self._age  8 def show_age(self):  9 return self._show_age() #此处的self不要少了 10 tk=Person("TK",24) 11 print(tk.show_age()) 12 13 """output 14 24 15 """

 1 #继承  2 class Car:#父类  3 def __init__(self,number_of_wheels,seating_capacity,maximum_velocity):  4 self.number_of_wheels=number_of_wheels  5 self.seating_capacity=seating_capacity  6 self.maximum_velocity=maximum_velocity  7 class ElectricCar(Car):#派生类  8 def __init(self,number_of_wheels_1,seating_capacity_1,maximum_velocity_1):  9 Car.__init__(self,number_of_wheels_1,seating_capacity_1,maximum_velocity_1) #利用父类进行初始化 10 11 my_electric_car=ElectricCar(4,5,250) 12 print(my_electric_car.number_of_wheels) 13 print(my_electric_car.seating_capacity) 14 print(my_electric_car.maximum_velocity) 15 16 """output 17 4 18 5 19 250 20 """