Question

如果用户希望购买另一项＆＃34;，当他们这样做时，新产品将替换CSV文件中的旧产品。

This is my blank CSV file when I purchase more than one item; only the latest item purchase goes on the stock file

This is my CSV file which contains all the product information:

我的任务是开发一个程序，在订单后更新库存水平。在库存文件中包括当前库存水平，重新订购水平和目标库存水平。该程序在被指示时应计算哪些产品缺货或低于重新订购水平。

这是我的代码：

import csv

option='yes'
while option=='yes':
    data=open('Product information.csv', 'rt')
    purchase=csv.reader(data)
    blank=open('Blank file.csv', 'wt')
    blank_read=csv.writer(blank)
    order=input('Please enter the GTIN-8 code of the product you would like to purchase: ')
    for row in purchase:
        for field in row:#
            if field==order:
                quantity=int(input('How much of that item: '))
                if quantity<=int(row[3]):
                    print('Your order has successfully been added')
                    difference=int(row[3])-int(row[4])
                    if quantity>=difference:
                        stock=int(row[3])-quantity
                        GTIN=row[0]
                        item=row[1]
                        price=row[2]
                        stock=row[3]
                        reorder=row[4]
                        target_stock=row[5]
                        blank_read.writerows([[GTIN,item,price,stock,reorder,target_stock]])

                    if quantity>int(row[3]):
                        print('You have exceeded the stock level')

    option=input('Do you want to purchase another item: ')
    blank.close()

另外，如何将最新的库存水平更新到我的空白CSV文件中，因为当用户购买商品时，当前库存将明显改变。对不起，如果我要求很多!!!

感谢您的帮助!!!!

Answer 1

您将在此处查看所有剩余的购买内容：

for order in purchase:
    if quantity>=difference:

删除for order in purchase:，它应该更好用：

import csv

option='yes'
while option=='yes':
    data=open('Product information.csv', 'rt')
    purchase=csv.reader(data)
    blank=open('Blank file.csv', 'wt')
    blank_read=csv.writer(blank)
    order=input('Please enter the GTIN-8 code of the product you would like to purchase: ')
    for row in purchase:
        for field in row:
            if field==order:
                quantity=int(input('How much of that item: '))
                if quantity<=int(row[3]):
                    print('Your order has successfully been added')
                    difference=int(row[3])-int(row[4])
                    if quantity>=difference:
                        stock=int(row[3])-quantity
                        GTIN=row[0]
                        item=row[1]
                        price=row[2]
                        stock=row[3]
                        reorder=row[4]
                        target_stock=row[5]
                        blank_read.writerows([[GTIN, item, price, stock,
                                              reorder, target_stock]])

                    if quantity>int(row[3]):
                        print('You have exceeded the stock level')

    option=input('Do you want to purchase another item: ')
    blank.close()

Answer 2

好的，所以我看到MikeMüller已经回答了你的问题。然而，作为迈克，我不太了解，我还花了一些时间来解决你的问题，然后才弄明白。然而，我想对迈克的回答做一些补充。

首先，我必须指出你的问题对我来说仍然不太清楚。一方面，你质疑为什么你得到重复的输出。迈克解释并告诉你为什么会这样。但与此同时，您指出“程序应该在被指示时计算哪些产品缺货或低于重新订购级别”，这与您的代码目前正在做的不完全相同。现在它只从当前库存stock=int(row[3])-quantity中提取所需的项目数量，但在写入新的CSV文档之前，只有几行后原始值被重置stock=row[3]。更重要的是，如果将if quantity<=int(row[3]):评估为true，则会打印出已成功添加订单的消息，但稍后当if quantity>=difference:返回false时，没有任何反应。

此外，你在同一个 if语句中启动一个if语句if quantity<=int(row[3]):和，你调用另一个if语句if quantity>int(row[3]):，根据你的第一个if语句import csv blank_file=open('Blank file.csv', 'w') data_file=open('Product information.csv', 'rt') do_purchase=csv.reader(data_file) def makeCSV(user_option): if user_option=="yes": new_order=input('Please enter the GTIN-8 code of the product you would like to purchase: ') global do_purchase for row in do_purchase: print ("row =", row[0]) if row[0]== new_order: total_quantity=int(row[3]) reorder_quantity=int(row[4]) target_quantity=row[5] required_quantity=int(input('How much of that item: ')) if required_quantity<=total_quantity: print("yes") max_order=total_quantity-reorder_quantity if required_quantity<=max_order: stock=total_quantity-required_quantity print("new stock =", stock) GTIN=row[0] item=row[1] price=row[2] reorder=row[4] target_stock=row[5] global blank_file blank_file_read=csv.writer(blank_file) blank_file_read.writerows([[GTIN,item,price,stock,reorder,target_stock]]) break else: print('Sorry, we can only deliver', max_order ,'items') break else: print("sorry, not enough in stock") break user_option=input('Do you want to purchase another item: ') if user_option == "yes": makeCSV("yes") else: blank_file.close() exit else: blank_file.close() exit makeCSV("yes")

所以，我一直在搞乱你的代码，这是我的替代方案（这仍然远非完美，但应该为你提供一些关于如何实现你的一些目标的进一步见解）：

initBooks(response) { console.log(this.state.books, "new books not set yet") let newBooks = [] for (let entry of response) { newBooks.push({ id: entry._id, name: entry.name, author: entry.author, description: entry.description, price: Number(entry.name), publisher: entry.publisher }) } this.setState({books: [...this.state.books, newBooks]}, () => { console.log(this.state.books, "new books set in the state") }) }

为什么我的代码会替换之前在CSV文件中订购的项目？

2 个答案: