Question

数据结构

myshelf = {}
myshelf["PY"] ={}
myshelf["PY"]["WWW"] = {"Name": "Book1", "Class": "5th"}
myshelf["PY"]["XXX"] = {"Name": "Book2", "Class": "6th"}
myshelf["EE"] ={}
myshelf["EE"]["YYY"] = {"Name": "Book3", "Class": "7th"}
myshelf["EE"]["ZZZ"] = {"Name": "Book4", "Class": "8th"}
print(myshelf) 
for shelfkey in myshelf.keys():
for subshelf in myshelf[shelfkey].keys():
    print(myshelf[shelfkey][subshelf])

这是上面代码的输出，这意味着我的数据结构还可以。

{'PY': {'WWW': {'Name': 'Book1', 'Class': '5th'}, 'XXX': {'Name': 'Book2', 'Class': '6th'}}, 'EE': {'YYY': {'Name': 'Book3', 'Class': '7th'}, 'ZZZ': {'Name': 'Book4', 'Class': '8th'}}}
{'Name': 'Book1', 'Class': '5th'}
{'Name': 'Book2', 'Class': '6th'}
{'Name': 'Book3', 'Class': '7th'}
{'Name': 'Book4', 'Class': '8th'}

现在我有一个csv文件，其中包含书籍，我想将所有书籍都放入我的书架中。注意myShelf具有SubShelf。 ShelfName是书名的2个字母大写，而我的Subshelf具有书号的ISBN。（考虑到特定书籍的ISBN号将保持不变，并且永远不会改变）

CSV文件格式

1   A11B12C13D14    Python Expert   English India   Raj     500 2
2   A11B12C13D14    Python Expert   English India   Raj     500 2
3   A11B12C13D14    Python Expert   English India   Raj     500 2
4   A11B12C13D16    Python Advanced English USA Amit    40000   1
5   A11B12C13D17    Aws Arch    English USA Sumit   40000   1

现在这是我的主要代码

import csv

class Book:

def __init__(self, isbn, name, language, origin, authors, price, version):
    self.isbn = isbn
    self.name = name
    self.language = language
    self.origin = origin
    self.authors = authors
    self.price = price
    self.version = version
    self.counter= 1


class Shelf:
    def __init__(self, mycsvfilepath):
        self.shelf = {}
        self.mycsvfilepath = mycsvfilepath


        def _add_books_(self):
    with open(self.mycsvfilepath, "rt") as my_csv_file:
        my_csv_reader = csv.reader(my_csv_file)
        for line in my_csv_reader:
            mykeyforshelf = line[2][0:2].upper()
            print("ShelfName ={}".format(mykeyforshelf))
            print("SubShelfName={}".format(line[1]))
            if mykeyforshelf not in self.shelf.keys():
                self.shelf[mykeyforshelf] = {}
                self.shelf[mykeyforshelf][line[1]] = Book(line[1],line[2],line[3],line[4],line[5],line[6],line[7])
                print("Added New Book to new shelf ={} , subshelf= {}, BookName= {}".format(mykeyforshelf,line[1],self.shelf[mykeyforshelf][line[1]].name))
                print(self.shelf)
                print("\n")
            elif line[1] in self.shelf[mykeyforshelf].keys():
                print("this is existing shelf = {} and subshelf={}".format(mykeyforshelf,line[1]))
                print("existing counter for this book = {}".format(self.shelf[mykeyforshelf][line[1]].counter))
                self.shelf[mykeyforshelf][line[1]].counter = self.shelf[mykeyforshelf][line[1]].counter + 1
                print("New counter for this book = {}".format(self.shelf[mykeyforshelf][line[1]].counter))
                print(self.shelf)
                print("\n")
            else:
                print("I am existing shelf = {} , But new Sub Shelf ={}".format(mykeyforshelf,line[1]))
                self.shelf[mykeyforshelf][line[1]] = Book(line[1],line[2],line[3],line[4],line[5],line[6],line[7])
                print(self.shelf)
                print("\n")


myShelfObj = Shelf("E:\\Ashish\MyCsvFiles\\myCurrentInventory.csv")
myShelfObj._add_books_()
print("_____________________________________________________________")
print(myShelfObj)
print(type(myShelfObj))

#for shelfkey in myShelfObj:
#    for subshelf in myShelfObj.shelfkey:
#        print(myShelfObj[shelfkey][subshelf])

myCode是工作文件，如果我保持3行以上的哈希标记。这是工作代码的输出。

ShelfName =PY
SubShelfName=A11B12C13D14
Added New Book to new shelf =PY , subshelf= A11B12C13D14, BookName= Python 
Expert
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>}}


ShelfName =PY
SubShelfName=A11B12C13D14
this is existing shelf = PY and subshelf=A11B12C13D14
existing counter for this book = 1
New counter for this book = 2
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>}}


ShelfName =PY
SubShelfName=A11B12C13D14
this is existing shelf = PY and subshelf=A11B12C13D14
existing counter for this book = 2
New counter for this book = 3
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>}}


ShelfName =PY
SubShelfName=A11B12C13D16
I am existing shelf = PY , But new Sub Shelf =A11B12C13D16
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>, 
'A11B12C13D16': <__main__.Book object at 0x000000FC39A1CA58>}}


ShelfName =AW
SubShelfName=A11B12C13D17
Added New Book to new shelf =AW , subshelf= A11B12C13D17, BookName= Aws Arch
{'PY': {'A11B12C13D14': <__main__.Book object at 0x000000FC39A1C940>, 
'A11B12C13D16': <__main__.Book object at 0x000000FC39A1CA58>}, 'AW': 
{'A11B12C13D17': <__main__.Book object at 0x000000FC39A1CAC8>}}


_____________________________________________________________________________
<__main__.Shelf object at 0x000000FC399C9748>
<class '__main__.Shelf'>

但是正如我上面提到的，如果我取消散列最后3行，则会给我以下提到的错误：

for shelfkey in myShelfObj:
TypeError: 'Shelf' object is not iterable

请帮助我。

Answer 1

输入myShelfObj类型时，您将看到自己的样子

print(type(myShelfObj))

这是输出

<class '__main__.Shelf'>

因此，您尝试遍历不可能的对象。您将收到此类错误。您只能将for循环用于列表元组字典，而不能用于对象。希望我清楚

带有字典的Python OOPS类

1 个答案: