dede from_unixtime函数如何正确使用？

Of course! Let's break down the dede:from_unixtime tag in DedeCMS (织梦内容管理系统).

What is dede:from_unixtime?

In simple terms, dede:from_unixtime is a DedeCMS template tag used to convert a Unix timestamp into a human-readable date and time format.

Why is this needed?

• Unix Timestamp: This is a number representing seconds since January 1, 1970 (UTC). It's how databases (like MySQL) and many programming systems store dates and times because it's efficient for sorting and calculations.
• Human-Readable Format: Website visitors don't see timestamps like 1678886400. They want to see March 15, 2025 or 2025-03-15 10:30:00.

The dede:from_unixtime tag acts as a translator, making the date stored in your database easy for users to understand.

Syntax and Parameters

The basic syntax of the tag is:

{dede:from_unixtime timestamp='你的时间戳' format='日期格式' /}

It has two main parameters:

timestamp (Required)

This is the Unix timestamp you want to convert. It's not always a static number. It's most commonly used to display the publication time of an article.

• Common value: [field:pubdate /] or [field:senddate /]
  • [field:pubdate /]: The article's publication date (from the pubdate field in the dede_archives table).
  • [field:senddate /]: The article's submission date (from the senddate field).

Example:

{dede:from_unixtime timestamp='[field:pubdate /]' /}

format (Optional)

This parameter controls the output format of the date and time. If you don't provide it, DedeCMS uses a default format (usually Y-m-d H:i:s).

Here are the most common format codes you can use:

Practical Examples

Let's assume an article's [field:pubdate /] is 1678886400, which corresponds to 2025-03-15 10:30:00.

Example 1: Default Format

If you don't specify a format, it will look like this:

{dede:from_unixtime timestamp='[field:pubdate /]' /}

Output:

2025-03-15 10:30:00

Example 2: Standard Date Format (e.g., for a list)

This is very common for displaying just the date of an article.

{dede:from_unixtime timestamp='[field:pubdate /]' format='Y-m-d' /}

Output:

2025-03-15

Example 3: More Readable Format (e.g., "March 15, 2025")

This is great for improving user experience.

{dede:from_unixtime timestamp='[field:pubdate /]' format='F j, Y' /}

Output:

March 15, 2025

Example 4: Including Time in 12-hour Format

Use this if you want to show AM/PM.

{dede:from_unixtime timestamp='[field:pubdate /]' format='Y-m-d h:i:s A' /}

Output:

2025-03-15 10:30:00 AM

Example 5: Displaying the Update Time

You can use it for other timestamps in the system, like the article's update time (uptime).

更新时间: {dede:from_unixtime timestamp='[field:uptime /]' format='Y-m-d H:i' /}

Output:

更新时间: 2025-03-16 16:45

Common Use Cases in Templates

1. In article_article.htm (Article Detail Page): Display the article's publication date in a user-friendly way.

   <div class="article-info">
       <span>发布时间：{dede:from_unixtime timestamp='[field:pubdate /]' format='Y-m-d' /}</span>
       <span>作者：{dede:field name='writer' /}</span>
       <span>来源：{dede:field name='source' /}</span>
       <span>点击：{dede:field name='click' /}</span>
   </div>

2. In list_artlist.htm (Article List Template): Show the date for each article in a list.

   {dede:list}
   <li>
       <a href="[field:arcurl/]">[field:title/]</a>
       <span class="date">{dede:from_unixtime timestamp='[field:pubdate /]' format='Y-m-d' /}</span>
   </li>
   {/dede:list}

Troubleshooting

• Problem: The tag shows nothing or a strange error.

  • Check 1: Make sure the timestamp parameter is correctly set, usually to [field:pubdate /]. Double-check that this field has a value in your database.
  • Check 2: Ensure you are using the correct DedeCMS tag syntax. The closing is important: {dede:from_unixtime ... /}.

• Problem: The date format is wrong.

  • Check: Review your format string. Remember that characters like , , , and spaces are treated as literal characters. Use the format codes from the table above correctly. For example, Y-m-d is correct, but Y m d would produce 2025 03 15.