Good, as an experienced website operations expert, I will combine the documentation of AnQiCMS (AnQiCMS) to explain in detail how to implement logical AND in templates.iftags to implement logical AND.&&orand）的多条件判断。

安企CMS模板中的逻辑与（&&orand）多条件判断：一份实用指南

In daily website content operations, we often need to dynamically display content or page elements based on different conditions.For example, a prominent 'Hot' tag will be displayed only when the article is marked as 'Recommended' and the reading volume exceeds a certain number; or a certain feature button will be shown only when the user is logged in and has specific permissions.Auto CMS provides strong support for implementing these complex logic judgments with its flexible template engine.

The template engine syntax of Anqi CMS is similar to Django, it uses a concise and efficient tag system to control the display of content. Among them,ifTags are the core tools for conditional judgments. When we need to satisfy multiple conditions simultaneously, we naturally think of using the logical AND operator.&&orandHowever, the template engine'sifThe syntax structure of the tag when using multiple condition judgments is slightly different from the direct connection method in our conventional programming languages. Understanding this point is crucial for efficiently utilizing the template function of AnQiCMS.

Understanding the Anqi CMS templateifBasic tags

Let's review the Anqi CMS template firstifThe basic usage of tags. According to the document description, conditional judgment is defined using single curly braces and percent signs, and an end tag is required{% endif %}to end. Its basic structure is as follows:

{% if 条件 %}
  <!-- 条件为真时显示的内容 -->
{% endif %}

You can also useelifandelseHandle more complex conditional branches:

{% if 条件1 %}
  <!-- 条件1为真时显示的内容 -->
{% elif 条件2 %}
  <!-- 条件2为真时显示的内容 -->
{% else %}
  <!-- 所有条件都不为真时显示的内容 -->
{% endif %}

For example, check if the document ID is 10:{% if archive.Id == 10 %}这是文档ID为10的文档{% endif %}This syntax is very intuitive and efficient for single condition judgments.

Logical AND (&&orand) clever usage

When multiple conditions need to be met at the same time, many users will try to do it directly inifuse a control character inside&&orandoperator, such as{% if condition1 && condition2 %}However, in the design of the template engine of AnQi CMS, operators like&&/and/||/orare{% if %}Tags conditional statements are usually not used directly to connect multiple independent condition expressions. They are more often designed toused in variable expressions (curly braces{{ }}）Inside boolean calculation.

This means, you cannot write it directly{% if item.Title == "重要文章" && item.Views > 100 %}. So how can you achieve multi-condition judgment? The answer lies inCompute the boolean operation result of multiple conditions in advance, and then use this result asifthe judgment condition of tags.

This can be achieved by{% set %}tags (variable assignment tag) to implement,{% set %}Allow you to create temporary variables and assign values to them in the template.

Suppose we want to implement a logic: Only when the article title contains the words "important"andWhen the number of page views exceeds 500, a special prompt is displayed. We can do it like this:

{% set is_featured_and_popular = (item.Title|contain:"重要") && (item.Views > 500) %}

{% if is_featured_and_popular %}
    <span class="badge badge-hot">热门推荐</span>
{% else %}
    <span class="text-muted">普通文章</span>
{% endif %}

In this example:

  1. We used{% set is_featured_and_popular = ... %}Defined a namedis_featured_and_popularboolean variable.
  2. in the expression on the right side of the equal sign,item.Title|contain:"重要"Determine whether the article title contains the word "important" (a filter is used here)containThe filter will return a boolean value).
  3. item.Views > 500Determine whether the article view count is greater than 500.
  4. Two boolean expressions are connected using the logical AND operator&&its result (trueorfalse) is assigned tois_featured_and_populara variable.
  5. Finally,{% if is_featured_and_popular %}we can then perform conditional judgments based on this pre-calculated boolean value.

Similarly, if you need to use logical OR (||oror) you can also use a similar method:

{% set is_special_or_new = (item.Flag == "a") || (item.CreatedTime > some_recent_timestamp) %}

{% if is_special_or_new %}
    <span class="label label-special">特荐或最新</span>
{% endif %}

This indirect but clear method perfectly solves the problem in AnQiCMS templateifThe need for multi-condition logical judgment in tags while maintaining the readability and maintainability of template code.

Practical scenarios and **practice

In actual operation, this multi-condition judgment skill can be applied to various scenarios:

  • Content display control:For example, decide whether to display the full content based on the user's VIP level and whether the article is paid.
  • [en] SEO Optimization:Only when the page TDK (title, keywords, description) is complete and the page content length meets the standard, the "SEO-friendly" indicator will be displayed.
  • Interactive elements:According to the user's login status and whether there are items in the shopping cart, decide whether to display the 'Go to checkout' button.

When using this method, there are several points to**pay attention to:

  • Variable naming should be clear:response for{% set %}Name the variables meaningfully, which can clearly express the logic they represent, for example:is_valid_user/can_display_promoetc.
  • Reasonable partitioning:For particularly complex logic, consider breaking large blocks of logic into multiple small boolean variables to improve readability.
  • Using Filters:Make full use of the various filters provided by the security CMS (such ascontain/lengthThey can help you more conveniently obtain and process data, providing a foundation for logical judgment.

Through these flexible applications, you will be able to finely control the presentation of AnQiCMS website content, creating a more intelligent and attractive user experience.

Common Questions (FAQ)

1. Why does trying to directly use{% if %}the label use&&orandfail when making multi-condition judgments?

This is because the template engine of AnQi CMS (similar to Django templates) uses{% if %}The label's condition part should be mainly regarded as an independent expression, not directly supporting multiple through&&orandconnected, mutually independent boolean conditions.&&andandMore logical operators are used in variable expressions{{ }}Performing boolean calculations internally, generating a finaltrueorfalseResults. Therefore, you need to first assign the boolean operation result of multiple conditions to a temporary variable (using){% set %}), and then use this temporary variable asifThe judgment condition of the label.

**2. In addition to using{% set %}Is there a more concise way to create temporary variables?