How to use `join` and `split` filters to process strings and arrays in the Anqi CMS template?

As an experienced CMS website operation personnel, I am well aware of the importance of flexible data handling in content management and display. The template engine of Anqi CMS provides a rich set of filters to help us achieve this goal, wherejoinandsplitThe filter is especially powerful when dealing with string and array data, allowing our content to be displayed more dynamically and accurately.

In daily content operation, we often encounter the need to display list data in a unified string format, or to split a string containing delimiters into independent items for processing.joinandsplitThe filter is designed to address these common scenarios.They allow us to effectively reorganize and transform data at the template layer without modifying the backend logic, thus meeting various front-end display needs.

In the Anq CMS template,joinFilter: Aggregate array into a string

joinThe filter is mainly used to concatenate all elements in an array or slice with a specified delimiter to form a single string.This is very useful when displaying multiple value fields, such as a document's multiple tags, a list of product features, or user-defined parameters.joinThis can help us quickly format it into a user-friendly string.

For example, suppose we have a variable in the templatearchive_tagsIt is a string array containing multiple tag names, such as["Go", "CMS", "AnQiCMS", "模板"]。如果我们希望在页面上将其显示为“Go, CMS, AnQiCMS, Template”，就可以使用joinFilter, and specify comma and space as delimiters:

<p>文档标签：{{ archive_tags|join:", " }}</p>

Whenarchive_tagsThe output will be when the variable is rendered:

<p>文档标签：Go, CMS, AnQiCMS, 模板</p>

This processing method avoids complex loop judgments and manual concatenation, greatly simplifies the template code, making content display more efficient.

In the Anq CMS template,splitFilter: Split the string into an array

WithjoinFilter function opposite,splitThe filter can split a string into an array of strings based on the specified delimiter.This is very practical in many scenarios, for example, if our document keywords are stored in a database field as a comma-separated string, and we want to extract each keyword independently, we may need to render it as a separate link or list item.

Assumearchive.Keywords字段存储的是“Go,CMS,AnQiCMS,模板”，我们想要将这些关键词分别显示为独立的元素，甚至为每个关键词生成一个链接。首先，我们可以使用EnglishsplitThe filter splits this string into an array:

{% set keyword_list = archive.Keywords|split:"," %}

Now,keyword_listit becomes an array of strings, for example["Go", "CMS", "AnQiCMS", "模板"]. We can then iterate over this array and process each keyword:

<div class="tags">
    {% set keyword_string = "Go,CMS,AnQiCMS,模板" %}
    {% set keyword_list = keyword_string|split:"," %}
    {% for kw in keyword_list %}
        <a href="/tag/{{ kw }}">{{ kw }}</a>
    {% endfor %}
</div>

In the actual security CMS template,archive.Keywordsit is usually a string. ThroughsplitFilter, we can easily convert it into an iterable array, thus realizing the independent display and link function of each keyword.

splitWithjoinCollaborative applications: flexible data conversion

In some cases,splitandjoinThe filter can be combined to achieve more complex data transformation requirements.This is especially effective when we need to process strings in the middle and then recombine them.For example, a string may contain multiple data blocks connected by different delimiters, and we may need to split them first, modify a certain part, and then reconnect them with a uniform delimiter.

a classic combination example is provided in the document, demonstrating how tosplitsplit a string, and thenjoinreconnect:

{% set my_data = "Hello, 99, 3.140000, good" %}
<p>{{ my_data|split:", "|join:"-" }}</p>

In this example, the string"Hello, 99, 3.140000, good"Firstly, go throughsplit:", "Split into an array["Hello", "99", "3.140000", "good"]Then, this array isjoin:"-"connected into a new string, using hyphens as the separator.-The final output will be:

<p>Hello-99-3.140000-good</p>

This combination provides great flexibility when dealing with free-form user input data or non-standard format data obtained from external APIs, helping us unify the data to adapt to front-end display.

Points to consider in practical applications

When usingjoinandsplitWhen filtering, pay attention to the data type.joinExpecting an array or slice,splitThen expect to receive a string.If the type passed in does not match, it may lead to template rendering errors or results that do not meet expectations.In addition, choosing the correct delimiter is crucial, whether for splitting or joining, it should ensure that the delimiter can accurately identify the data boundaries.

PassjoinandsplitThese two seemingly simple yet powerful filters bring higher flexibility and efficiency to our website operations for Anqi CMS.They make it possible for us to control the presentation of content more conveniently, whether it is for aggregation display or decomposition processing, it can be easily handled, thus providing users with a better browsing experience.

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Common Questions and Answers (FAQ)

1.joinandsplitFilter supports processing other data types other than strings and arrays?

No,joinThe filter is mainly designed to concatenate the elements of an array (or slice) into a string,splitThe filter is used to split strings into an array. If the data type passed does not match the expected type, for example passing a number directly tosplitFilter, may cause template rendering errors or unclear results. Please ensure the data type of the variable is as expected by the filter before using it.

2. If in usesplitWhat happens if the specified delimiter in the filter does not exist in the target string?

WhensplitThe filter does not throw an error when it tries to find a specified delimiter in a string but fails.Instead, it returns an array containing the original string as the only element."AnQiCMS"while the specified delimiter is","the result will be an array["AnQiCMS"]This behavior is usually expected, as it ensures that a traversable array is always obtained in any case.

3. Can these two filters be used on any variable in the security CMS template?

Yes, as long as the data type of the variable matchesjoinorsplitThe expected input type of the filter matches, which can be used on any variable in the Security CMS template. This means it can be used whether it is a variable passed directly from the backend, data obtained through other template tags, or used within the template.setLabel-defined temporary variables, which can be applied to these filters as long as they are of string or array type.