用python文本中的变量覆盖特定列中的值

Question

我正在制作这个程序，以便用户输入一些内容，该内容存储为变量，然后用该变量覆盖文本文件中特定列中的值。 我总是遇到问题 TypeError: 'int' object is not callable 这是我需要帮助的代码。

with open("Base.txt", "r") as f:#opening it as variable f makes it easier to call to later
        searchlines = f.readlines()#shortens the function f.readlines() to searchlines. This is easier to reference later
        infile = open("Base.txt","r+")#opens the file in reading mode
        liness = infile.readlines()#makes the variable liness to be the same as reading lines in the file
        liness =    ', '.join(liness)#adds commas onto liness, which is equal to new liness
        liness = liness.split(" ")#breaks apart the quotations
        for i, line in enumerate(searchlines):
            if barcode in line:
                words = line.split(" ")#sets the word variable to split the line into quotes
                howmany =int(input("How many are your buying? "))
                quantity=int(words[3])
                if howmany < quantity:
                    with open("Base1.txt","w") as p:
                        quantity=int(words[3])
                        update=int(quantity-howmany)
                        p.write(quantity[update])
                        break

我的整个代码是

    import sys
import string
x = 0
menu = 0
recipt = open("Recipt.txt","r+")
recipt.seek(0)
recipt.truncate()
recipt.close()
total = 0#Makes the variable total 0, this makes it easier to work with later
while x == 0:
    menu = input("What do you want to do?\n 1)Add to the Recipt \n 2)View the Recipt \n 3)Checkout \n")#Gives the user a choice
    if menu ==  "1":
        recipt = open("Recipt.txt","a")#opens an empty text file. This will be the receipt
        y = 0
        while y == 0:
            barcode = input("What is the barcode of the item? ")
            if len(barcode) == 8:
                searchfile = open("Base.txt", "r+")#Opens the premade database file
                y = y + 1
            else:
                print("That barcode is not 8 in length.")
        with open("Base.txt", "r") as f:#opening it as variable f makes it easier to call to later
            searchlines = f.readlines()#shortens the function f.readlines() to searchlines. This is easier to reference later
            infile = open("Base.txt","r+")#opens the file in reading mode
            liness = infile.readlines()#makes the variable liness to be the same as reading lines in the file
            liness =    ', '.join(liness)#adds commas onto liness, which is equal to new liness
            liness = liness.split(" ")#breaks apart the quotations
            for i, line in enumerate(searchlines):
                if barcode in line:
                    words = line.split(" ")#sets the word variable to split the line into quotes
                    howmany =int(input("How many are your buying? "))
                    quantity=int(words[3])
                    if howmany < quantity:
                        with open("Base1.txt","w") as p:
                            update=str(quantity-howmany)
                            p.write(str(quantity))
                            break
                        break
                    elif howmany==quantity:
                        update=0
                        p.write(str(update))
                        break
                    elif howmany>quantity:
                        print("We do not have that many!")
                        continue
                    line = line.replace('\n', '')#replaces line with a new line and a space
                    recipt.write(line + ' ' + howmany)#writes into the new file with the variable line and how many with a space in between
                    howmany = float(howmany)#turns the howmany variable into a float,decimal
                    prices = words[2]#prices is equal
                    prices = float(prices) 
                    totalprice = prices * howmany
                    totalprice = ("{0:.2f}").format(round(totalprice,2))
                    recipt.write(" £" + totalprice + "\n")
                    total = float(total) + float(totalprice)

                    recipt.close()
                elif barcode not in liness:
                    print("Item not found.")      
    if menu ==  "2":
        with open("Recipt.txt","r+") as f:
            for line in f:
                print(line)
        recipt.close()
    if menu ==  "3":
        recipt = open("Recipt.txt","a")
        recipt.write("£"+str(total))
        recipt.close()
        sys.exit()

错误信息。

Traceback (most recent call last):
  File "C:\Users\David\Desktop\Task 2 2 Version 2.py", line 37, in <module>
    p.write(quantity(update))
TypeError: 'int' object is not callable

如果需要的话。 我尽量不使用 csv，所以请不要用它作为答案。 我正在使用 python 3.5。 谢谢。

Answer 1

您需要解决一些错误，我已对它们进行了评论。 在这两种情况下，它们都围绕您的可变quantity 。 数量是一个整数，这意味着你不能做quantity[value], quantity(value), quantity.function

quantity=int(words[3])
if howmany < quantity:
    with open("Base1.txt","w") as p:
        quantity=int(words[3])
        update=int(quantity-howmany)
        p.write(quantity[update])     #### quantity is an int, so this is the reason for your initial exception, you cannot index into quantity
        break
    break
elif howmany==quantity:
    update=0
    quantity.write(update)       ### this is another exception causing bug
    break

您不能对变量数量调用 .write()，因为它是一个整数

你评论说不知道回溯是什么，这是一个例子：

>>> a = 5
>>> a.write(3)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'int' object has no attribute 'write'