Question

在我的应用程序中，用户可以创建有效期为100天的帖子。现在，我想向用户显示还剩多少天，直到他的帖子被删除。我目前正在解决芹菜工作对工作的实际删除。我的问题只是关于如何显示数字，直到有效性用完为止。我认为我只需要一个IntegerField，其有效期为几天，然后从创建日期开始减去它。

有一种实用的方法吗？

models.py

class Post(models.Model):
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    title = models.CharField(verbose_name="Post Title", max_length=40)
    content = models.TextField(verbose_name="Post Content", max_length=5000)
    tag = models.CharField(verbose_name="Tags/Meta - (sep. by comma)", max_length=50, blank=True)
    category = models.ForeignKey(Category, verbose_name="Category", on_delete=models.CASCADE, null=True)
    post_type = models.CharField(default='Free', editable=False, max_length=4)
    postattachment = fields.FileField(
        verbose_name="Post Attachment",
        blank=True,
        null=True,
        upload_to=get_file_path_user_uploads,
        validators=[file_extension_postattachment, file_size_postattachment]
    )
    postcover = fields.ImageField(
                              null=True,
                              blank=True,
                              upload_to=get_file_path_user_uploads,
                              validators=[default_image_size, default_image_file_extension],
                              dependencies=[FileDependency(processor=ImageProcessor(
                                  format='PNG', quality=99, scale={'max_width': 700, 'max_height': 700}))])
    up_vote = models.IntegerField(verbose_name='Post Up-Vote(s)', default=0)
    down_vote = models.IntegerField(verbose_name='Post Down-Vote(s)', default=0)
    published_date = models.DateField(auto_now_add=True, null=True)

感谢和亲切问候

更新

models.py

...
    down_vote = models.IntegerField(verbose_name='Post Down-Vote(s)', default=0)
    published_date = models.DateField(auto_now_add=True, null=True)

    def days_remaining(published_date):
        """
        Returns the remaining days from 'published_date' + 100 days until today.
        """
        return published_date + datetime.timedelta(days=100) - datetime.time.today()

template.html

...
<td>{{ post.days_remaining }}</td>
....

Answer 1

您可以在模型中定义一个方法来计算，如下所示：

class Post(models.Model):
    # ...
    published_date = models.DateTimeField(auto_now_add=True, null=True)

    def get_time_diff(self):
        current_time = datetime.datetime.now()
        delta = current_time-self.published_date
        return delta.days

在您的代码或模板中使用此方法：

post = Post(...)
if post.get_time_diff > 30:
    # do something

更新：如果要计算剩余天数，可以在模型中添加另一个字段（例如days_threshold），该字段可以保存以下整数：

class Post(models.Model):
    # ...
    days_threshold = models.IntegerField(default=100)
    # ...

在您的get_time_diff方法中，您可以编写如下内容：

def get_time_diff(self):
    current_time = datetime.datetime.now()
    delta = current_time-self.published_date
    remaining_days = self.days_threshold - delta.days
    if remaining_days >= 0
        return remaining_days
    return 0  # for non negative results in day

或者您可以在方法中添加以此类推的硬编码的days_threshold：

def get_time_diff(self):
    current_time = datetime.datetime.now()
    delta = current_time-self.published_date
    remaining_days = 100 - delta.days  # I think this is bad practice but works
    if remaining_days >= 0
        return remaining_days
    return 0  # for non negative results in day

Answer 2

由于您已经在模型中发布了date_date，因此可以找出发布日期。例如

from datetime import datetime

diff = datetime.now() - published_date

现在，如果max_days = 100（根据您），那么您可以简单地执行max_days-diff.days将是您的预期结果。

希望对您有帮助。

Answer 3

您可以执行以下操作：

models.py

from django.db import models
import datetime


# Create your models here.
class Post(models.Model):
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    title = models.CharField(verbose_name="Post Title", max_length=40)
    content = models.TextField(verbose_name="Post Content", max_length=5000)
    tag = models.CharField(verbose_name="Tags/Meta - (sep. by comma)", max_length=50, blank=True)
    category = models.ForeignKey(Category, verbose_name="Category", on_delete=models.CASCADE, null=True)
    post_type = models.CharField(default='Free', editable=False, max_length=4)
    postattachment = fields.FileField(
        verbose_name="Post Attachment",
        blank=True,
        null=True,
        upload_to=get_file_path_user_uploads,
        validators=[file_extension_postattachment, file_size_postattachment]
    )
    postcover = fields.ImageField(
        null=True,
        blank=True,
        upload_to=get_file_path_user_uploads,
        validators=[default_image_size, default_image_file_extension],
        dependencies=[FileDependency(processor=ImageProcessor(
            format='PNG', quality=99, scale={'max_width': 700, 'max_height': 700}))])
    up_vote = models.IntegerField(verbose_name='Post Up-Vote(s)', default=0)
    down_vote = models.IntegerField(verbose_name='Post Down-Vote(s)', default=0)

    published_date = models.DateField(auto_now_add=True, null=True)

    @property
    def remaining_days(self):
        """
        Returns the remaining days defined as: 'published_date' + 100 days - today.
        """
        return (self.published_date + datetime.timedelta(days=100) - datetime.date.today()).days

views.py

from django.views import generic
from .models import Post
class PostDetailView(generic.DetailView):
    model = Post
    template_name = "post_detail.html"

post_detail.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Post Detail</title>
</head>
<body>
<p><strong>Days remaining:</strong> {{ post.remaining_days }}</p>

</body>
</html>

屏幕截图：

Django有效期计数器

3 个答案: