Python 学习过程问题记录

一:   学习类和对象中的问题

 

1.  写类的时候,我会按流程图先把各个方法,属性和参数先注释好,然后去填充代码.不过每个方法写完,下面要写个pass,要不会报错:

     错误代码: IndentationError: expected an indented block 

 1 class auto_order:
 2     order={'湘菜':['1: 攸县香干','2: 农家一碗香'],'川菜':['1: 重启小面','2: 麻辣小龙虾'],'最近菜系':[]}
 3     
 4     #类参数
 5     def __init__(self,cai_class):
 6         self.cai_class = cai_class
 7     
 8     #点菜操作
 9     def order_select(self,order_con = True):  #方法下是空的,返回 IndentationError: expected an indented block.
10 
11 order_me = auto_order('湘菜')
12 print(order_me.order)

 

2. continue后面行代码不执行

    我写了一个方法,比如点菜,我想把点菜的结果返回,然后怕代码有错误,然后在continue下面加了print,想打印看看是否拿到值,结果不打印.

    报错代码:  无报错,  continue直接结束了方法运行.

    

 1 class auto_order:
 2     order={'湘菜':['1: 攸县香干','2: 农家一碗香'],'川菜':['1: 重启小面','2: 麻辣小龙虾'],'最近菜系':[]}
 3 
 4     #类参数
 5     def __init__(self,cai_select):
 6         self.cai_select = cai_select
 7         
 8     
 9     #菜单调用
10     def menu_show(self):
11         self.cai_names = self.order[self.cai_class]
12         for cai_name in self.cai_names:
13             print(cai_name)
14     
15     #点菜操作
16     def order_select(self,order_con = True):
17         if order_con == True:
18             cai_select = input('请选择菜系: \n')
19             
20         
21         elif order_con == False:
22             cai_select = input('请输入菜名: \n')
23         
24         return cai_select
25         print(cai_select)
26         
27         
28 
29 
30 
31 order_me = auto_order('湘菜')
32 order_me.order_select(False)

返回结果未执行25行print语句:

所以代码修改如下:

class auto_order:
    order={'湘菜':['1: 攸县香干','2: 农家一碗香'],'川菜':['1: 重启小面','2: 麻辣小龙虾'],'最近菜系':[]}

    #类参数
    def __init__(self,cai_select):
        self.cai_select = cai_select
        
    
    #菜单调用
    def menu_show(self):
        self.cai_names = self.order[self.cai_class]
        for cai_name in self.cai_names:
            print(cai_name)
    
    #点菜操作
    def order_select(self,order_con = True):
        if order_con == True:
            cai_select = input('请选择菜系: \n')
            
        
        elif order_con == False:
            cai_select = input('请输入菜名: \n')
        
        print(cai_select)
        return cai_select
        
        
        



order_me = auto_order('湘菜')
order_me.order_select(False)

返回结果,执行了print语句:

 

 

     

posted @ 2019-07-30 16:59  一克拉小猎  阅读(149)  评论(0)    收藏  举报