In the daily content operation of Anqi CMS, we often need to process strings in various ways, among which case conversion is one of the common requirements.The AnQi CMS is developed based on Go language, and its template engine supports a rich set of filter functions, which can conveniently implement these operations.However, when dealing with strings containing Chinese or other non-English characters, the behavior of these case conversion filters may be different from when dealing with English characters. Understanding this is very important for ensuring that the content is displayed correctly.

English translation: The template and filter basics of AnQi CMS

The template system of Anqi CMS adopts syntax similar to Django template engine, which allows content managers and front-end developers to present and process data obtained from the backend in a straightforward manner.Among them, Filters are a powerful feature of the template, which allows us to perform various transformations on variables.{{ 变量名|过滤器名称:参数 }}It is a commonly used syntax structure.Through these filters, we can easily format dates, slice strings, perform simple mathematical operations, of course, including string case conversion.

Overview of the string case conversion filter

In the template system of AnQi CMS, the following filters are mainly provided for converting the case of English strings:

  • upperThis filter will convert all the English letters in the string to uppercase.
  • lower: withupperOn the contrary, it will convert all the English letters in the string to lowercase.
  • capfirstThis filter will convert the first English letter of the string to uppercase, while keeping other characters unchanged.
  • titleThis filter is relatively complex; it converts the first letter of each word in a string to uppercase and the other letters to lowercase, and is usually used for title formatting.

These filters perform very directly and as expected when handling pure English strings. For example, applying "hello worldupper会得到“HELLO WORLD”，应用capfirst会得到“Hello world”。

非英文字符串的转换行为探究

However, when these case conversion filters are applied to strings containing Chinese or other non-English characters (such as Japanese, Korean, Russian, etc.), their behavior will change.

The core conclusion is:When these case conversion filters are applied to strings containing Chinese or other non-English characters, they usually do not perform case conversion on the non-English characters themselves.

This is because languages like Chinese, whose characters do not have the concept of 'uppercase' or 'lowercase'.Go language provides good support for Unicode character sets in its design, and the template engine of AnyQ CMS inherits this feature.When the filter detects a character that does not belong to the Latin alphabet category, it recognizes that the character does not have a corresponding uppercase or lowercase form, and therefore it will retain the original form of the character without making any modifications.

Let us illustrate this with several examples:

  • capfirstFilter and Chinese:{{ "安企内容管理系统"|capfirst }}The output will be:安企内容管理系统As can be seen, even if appliedcapfirst, there is no change in the Chinese string.

  • lowerFilter and Chinese:{{ "你好世界"|lower }}The output will be:你好世界Similarly, Chinese characters are not converted to lowercase because they do not have a lowercase form.

  • upperFilter and Chinese:{{ "你好世界"|upper }}The output will be:你好世界WithlowerSimilarly, Chinese characters are not converted to uppercase.

  • titleFilter and Chinese:{{ "你好世界"|title }}The output will be:你好世界Even for the conversion of the first letter of the wordtitleFilter, it is also ineffective for Chinese string.

This is very important.It means that in AnQi CMS, if you need to handle multilingual content and involve case conversion, these filters will only take effect on the English letters part, and keep the Chinese and other non-English characters unchanged.This design is reasonable and conforms to linguistic standards, ensuring the integrity and original semantics of non-English strings.

The Anqi CMS uses UTF-8 encoding for template files when processing content, which provides a solid foundation for the system to correctly identify and handle various language characters, thus avoiding common issues such as garbled characters.

Consideration of practical application scenarios

Understanding the behavior of these filters has practical guidance for content management and template design in our security CMS:

  • Consistency in content display：We can safely use these filters in the template to process dynamic content containing multiple languages without worrying that non-English characters such as Chinese will be accidentally modified, causing display errors or semantic errors.
  • URL structure and SEO：Although the filters discussed in this article do not directly affect URL generation, Anqi CMS has also optimized the URL structure for multilingual support in English.For example, when customizing the URL alias, the system will automatically generate the pinyin based on the Chinese title, rather than performing case conversion, which is more friendly to search engines.
  • Multilingual site managementEnglish: The CMS supports multilingual sites.When building a site that contains both English and Chinese content, we can apply the case conversion filter to the English content selectively, while ensuring the original presentation of Chinese content. This makes the management of multilingual content more flexible and accurate.

Summary

Common Questions (FAQ)

Q1: Why does my Chinese title use|upperAfter the filter, the uppercase is not displayed on the page?

A1:This is because Chinese characters themselves do not have uppercase and lowercase distinctions. The case conversion filters of Anqi CMS (such asupper/lower/capfirst/title主要针对拉丁字母（英文字母）设计，当它们遇到中文或其他非英文字符时，会保持这些字符的原始形态，不进行任何转换。

Q2：Do these case conversion filters affect the URL aliases or file paths on my website?

A2：It usually will not directly affect.English CMS generates URL aliases automatically based on Chinese titles and converts them into pinyin (for example, from “安企CMS” to “anqicms” or “an-qi-cms”), and these pinyin aliases are usually stored and used in lowercase.Therefore, the content filter mainly acts on the content display level, rather than the generation logic of URLs or file paths.But in rare cases, if the URL alias or file path directly uses variables that may contain English characters and has not been normalized, it may theoretically be affected, but this is not a common situation, and it is recommended to manage it uniformly through the pseudo-static rules and URL customization features of the background.

Q3：How can I ensure that the case format is consistent when my website displays multi-language content (for example, both English and Chinese)?

A3:For English characters, you can use as neededupper/lower/capfirstortitleFilter to unify its case format.For example, all product names are displayed in uppercase in the navigation.For Chinese or other non-English characters, as they do not have case distinctions, you only need to ensure the consistency of the text format when entering the content.The template system of Anqi CMS will respect the original display method of these non-English characters and will not perform any additional conversion.