影视目录卡片的语义层次：从未知值到可访问的 HTML 与 CSS

The structure of directory cards in video platforms involves understanding the semantic hierarchy, ranging from unknown values to accessible HTML and CSS. The process begins by examining a single component on a webpage, observing the exposure of field semantics. For example, a "Today's Focus" entry on a platform displays year, region, language, and "original film" without numeric values, while a selection section shows only the film title, format, and year.

Another platform displays the updating status of drama series, highlighting the need to differentiate between missing values and zeros, updated labels and commitments, or distinguishing between different parts of the same work. The article emphasizes the importance of receiving fields with their sources rather than the renderer inferring data when rendering.

It suggests defining a minimal model where the title is the original text, year can be an integer or null, statusText retains the original catalog tag, and observedAt records the observation time. Missing years should be represented as null, and the display layer should decide how to indicate them. A function is provided to display the year, which returns the year if it's an integer and not 1888, or "待核对" if the year is null, out of range, or in parentheses.

The article also discusses the use of explicit unknown values to establish data contracts, using title as the page content in its original form, year as an integer or null, statusText to save the original catalog tag, and observedAt for the observation time. The function to display the year is designed not to automatically convert strings to numbers in the presentation layer but to handle exceptions and input constraints.