django循环计数器中断 [英] django for loop counter break

问题描述

希望这是一个快速/容易的。我知道一种通过自定义模板标签来解决这个问题的方法，但是如果还有其他方法，我很好奇。我为我的博客创建了一个图库功能，我有一个画廊列表页面，分页我的所有画廊。现在，我不想显示该列表中每个图库的所有照片，因为如果每个图库甚至有20张图像，那么如果我在5个帖子中分页，则该页面上的100张图像。这是浪费的，错误的方式去处理事情。

我的问题是，有没有办法只显示照片集中的3张照片？我想做什么，但我不认为可能是（伪代码）：

  {％for gallery.photo_set％} 
 {％if forloop.counter lt 3％} 
< img src ={{photos.url}}> 
 {％endif％} 
 {％endfor％} 
  

从文档，除非我完全缺少它，这是不可能通过模板系统。因此，我可以编写自己的模板标签来解决它。我可能从观点来做点什么，但是我并没有想到这一点。另一个选项是给模型一个预览字段，并允许用户在预览字段中选择他们想要的照片。

无论如何，有几个不同的选择，所以我以为我会轮询观众看看你会怎么做。任何意见是赞赏。

解决方案

使用：

  {％for gallery.photo_set | slice：：3％} 
  

This is hopefully a quick/easy one. I know a way to work around this via a custom template tag, but I was curious if there were other methods I was over looking. I've created a gallery function of sorts for my blog, and I have a gallery list page that paginates all my galleries. Now, I don't want to show all the photos of each gallery in that list, since if each gallery even has 20 images, then that's 100 images on a page if I paginate at 5 posts. That'd be wasteful, and the wrong way to go about things.

The question I have is, is there a way to just display 3 photos from the photo set? What I'd like to do, but I don't think is possible is something like (pseudocode):

{% for photos in gallery.photo_set %}
   {% if forloop.counter lt 3 %}
     <img src="{{ photos.url }}">
   {% endif %}
{% endfor %}

Judging from the documentation, unless I'm completely missing it, that's not possible via the templating system. Hence, I can just write my own template tag of sorts to work around it. I could probably do something from the view aspect, but I haven't looked to far into that idea. The other option I have is giving the model a preview field, and allow the user to select the photos they want in the preview field.

Anyways, a few different options, so I thought I'd poll the audience to see how you'd do it. Any opinion is appreciated. Personally, enjoying that there's numerous ways to skin this cat.

解决方案

Use:

{% for photos in gallery.photo_set|slice:":3" %}

这篇关于django循环计数器中断的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！