Flask If 语句 - 列表索引的范围

Question

customer_data.json（加载为 customer_data）

{
  "customers": [
    {
      "username": "anonymous",
      "id": "1234",
      "password": "12341234",
      "email": "1234@gmail.com",
      "status": false,
      "books": [
        "Things Fall Apart",
        "Fairy Tales",
        "Divine Comedy"
      ]
    }
  ]
}

new_catalog.json 中的示例 post。（加载为 posts）

{
  "books": [
    {
      "author": "Chinua Achebe",
      "country": "Nigeria",
      "language": "English",
      "link": "https://en.wikipedia.org/wiki/Things_Fall_Apart\n",
      "pages": 209,
      "title": "Things Fall Apart",
      "year": 1958,
      "hold": false
    }
}

Flask_practice.py

中的必要代码

    for customer in customer_data['customers']:
        if len(customer['books']) > 0:
            for book in customer['books']:
                holds.append(book)
    
    for post in posts['books']:
        if post['title'] == holds[range(len(holds))]:
            matching_posts['books'].append(post)

holds[range(len(holds))] 无效。

我正在尝试使用 holds[0], holds[1] 等浏览 holds 中的每一本书，并测试 title 是否等于 [=17= 中的书名].

我对 Flask、Stack Overflow 和一般编码还是个新手，所以这个问题可能有一个非常简单的解决方案。

Answer 1

I am trying to go through each of the books in holds using holds[0], holds[1] etc and test to see if the title is equal to a book title

几乎直译为 Python：

# For each post...
for post in posts['books']:
    # ...go through each of the books in `holds`...
    for hold in holds:
        # ...and see if the title is equal to a book title
        if post['title'] == hold:
            matching_posts['books'].append(post)

或者，如果您不想 append(post) holds 中的每个项目：

for post in posts['books']:
    if post['title'] in holds:
        matching_posts['books'].append(post)

Flask If 语句 - 列表索引的范围

Flask If Statement - Range for list index

python

if-statement

range

flask