Question

我正在创建一个简单的应用程序，您可以在其中投票和支持不同的帖子。我在Python / Django中构建它...我通过将用户ID和注释ID存储到Upvote模型中获得upvote / downvote计数，并且通过关联计数为1.它打印出正确的数字。查看除了打印计数的次数被投票的次数。例如，如果它的1将打印：1，但是如果它的3将打印：3 3 3.如何更改我的逻辑以便它只打印出一次数字？

查看页面：

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <title>Topic</title>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
</head>
<body>
    <div class="container">
    <a href="/dashboard">Dashboard</a>
    <a href="/logout">Logout</a>
    <hr>
        <a href="/users/{{topic.user.id}}/">{{topic.user.first_name}} </a>posted a topic:
        <hr>
        Topic: {{topic.topic}}
        <br>
        Description: {{topic.description}}
        <hr>
        <h3>Post your answer</h3>
        <form action="/topic/{{topic.id}}/post" method="post">
            {%csrf_token%}
            <textarea name="comment" id="" cols="20" rows="2" required style="resize:none"></textarea>
            <br>
            <input type="submit" value="Post">
        </form>
        <hr>
        {% for comment in comments %}
            <a href="/users/{{comment.user_id}}/">{{comment.user.first_name}}</a>: {{comment.comment}}
            <br>
                <a href="/delete/{{comment.id}}/">Delete Post</a>
                <h5>Number of upvotes:</h5>
            {% for upvote in upvotes %}
                {% if upvote.comment_id == comment.id %}
                        {{upvotes.count}}
                {%endif%}
            {%endfor%}
                <h5>Number of downvotes: </h5>
            {% for downvote in downvotes %}
                {% if downvote.comment_id == comment.id %}
                    {{downvotes.count}}
                {%endif%}
            {%endfor%}  
            <hr>
            <a href="/upvote/{{comment.id}}/"><button>Upvote</button></a>
            <a href="/downvote/{{comment.id}}/"><button>Downvote</button></a>
            <br>
            <form action="/idea/{{comment.id}}/" method="post">
            {%csrf_token%}
            <textarea name="idea" id="" cols="20" rows="2" required style="resize:none"></textarea>
            <br>
            <input type="submit" value="Comment">
            </form>
                {% for idea in ideas %}
                    {% if idea.comment_id == comment.id %}
                        <a href="/users/{{idea.user_id}}/">{{idea.user}}</a> 
                        says: {{idea.idea}}
                        <a href="/delete/{{idea.id}}/comment">Delete Comment</a>
                    {%endif%}
                {%endfor%}
        {%endfor%}
    </div>
</body>
</html>

Answer 1

鉴于你的代码

    {% for upvote in upvotes %}
            {% if upvote.comment_id == comment.id %}
                    {{upvotes.count}}
            {%endif%}
    {%endfor%}

您最终打印upvotes.count upvotes次。你可以完全摆脱整个for循环，只需使用{{upvotes.count}}。

Answer 2

现在这是我的函数...试图在函数中递增一个名为counter ...的函数。在模型中将它作为一个整数字段，默认值为0

def upvote(request, comment_id):
    print "upvoting comment"
    user = User.objects.get(id=request.session['user_id'])
    comment = Comment.objects.get(id=comment_id)
    upvote = Upvote()
    counter = 1
    upvote.comment = comment
    upvote.user = user
    upvote.created_at = timezone.now()
    upvote.counter = upvote.counter + 1
    upvote.save()
    print upvote.counter
    return redirect('/dashboard')

和模型......

class Upvote(models.Model):
    user = models.ForeignKey(User, related_name="upvote_user", null=True)
    comment = models.ForeignKey(Comment, related_name="comment_upvote", null=True)
    counter = models.IntegerField(null=True, blank=False, default=0)
    created_at = models.DateField(null=True)
    class Meta:
        db_table = 'upvote'

views.py为模板渲染函数..

def show_topic(request, topic_id):
    print "Showing a topic"
    topic = Topic.objects.get(id=topic_id)
    comments = Comment.objects.all().filter(topic=topic)
    upvotes = Upvote.objects.all()
    ideas = Idea.objects.all()
    downvotes = Downvote.objects.all()
    context = {'upvotes': upvotes, 'ideas': ideas, 'comments': comments, 'topic': topic,'downvotes': downvotes}
    return render(request, 'discussionboard/show.html', context)

如何在Python中获得独特的数量？

2 个答案: