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| == Description ==
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| == 描述 == | | == 描述 == |
| At some point in your WordPress development career you may be presented with the need to display one or more posts using [[WordPress:Wikipedia:SELECT|SELECT]] criteria not provided by WordPress' [[WordPress:Template Tags/query posts | query_posts]] architecture. For instance, it may become necessary to [[WordPress:Wikipedia:JOIN|JOIN]] WordPress tables to determine which posts should be displayed, or you may want to use data stored in your own tables to determine which [[WordPress:Writing Posts|posts]] should be displayed.
| | 在你的WordPress发展历程的某个时刻,或许你需要通过非WordPress的[[WordPress:Template Tags/query posts | query_posts]] 架构提供的[[WordPress:Wikipedia:SELECT|选择]]标准来显示一篇或更多的文章。例如,你有时或许必须[[WordPress:Wikipedia:JOIN|加入]] WordPress表格以确定要显示的文章或使用自己表格中的储存数据来确定要显示[[WordPress:Writing Posts|正在写的文章]]。 |
| 在你的WordPress发展历程的某个时刻,或许你需要通过非WordPress的[[WordPress:Template Tags/query posts | query_posts]] 架构提供的[[WordPress:Wikipedia:SELECT|SELECT]]标准来显示一篇或更多的文章。例如,你有时或许必须[[WordPress:Wikipedia:JOIN|JOIN]] WordPress表格以确定要显示的文章或使用自己表格中的储存数据来确定要显示的[[WordPress:Writing Posts|posts]]。 | |
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| The practical example, outlined below, demonstrates a process of selecting all posts with a particular [[WordPress:Using Custom Fields | Custom Field]] value stored, and displaying them in a [[WordPress:Pages|Page]] based on a [[WordPress:Pages#Creating_your_own_Page_Templates|Page Template]]. Originally, this code was used to implement a post tagging [[WordPress:Plugins|plugin]], which allowed organizing posts in less structured collections than the WordPress [[WordPress:Manage_Categories_SubPanel|Categories]]. Your own usage may be very different, but the content and example should still give you a useful introduction to the general process involved.
| | 以下概述的实例展示了这样一个过程:选择有[[WordPress:Using Custom Fields | 定制区域]]存入值的所有文章并把它们在建立在[[WordPress:Pages#Creating_your_own_Page_Templates|页面模板]]基础上的[[WordPress:Pages|页面]]显示出来。这些编码最初用来执行文章标签[[WordPress:Plugins|插件]],它允许以比WordPress[[WordPress:Manage_Categories_SubPanel|分类]]稍无序的构架来组织文章。你的使用或许有所不同,但以下的例子仍会给你提供些有用的一般过程说明。 |
| 以下概述的实例展示了这样一个过程:选择有[[WordPress:Using Custom Fields | Custom Field]]存入值的所有文章并把它们在建立在[[WordPress:Pages#Creating_your_own_Page_Templates|Page Template]]基础上的[[WordPress:Pages|Page]]显示出来。这些编码最初用来执行文章标签[[WordPress:Plugins|plugin]],它允许以比WordPress[[WordPress:Manage_Categories_SubPanel|Categories]]稍无序的构架来组织文章。你的使用或许有所不同,但以下的例子仍会给你提供些有用的一般过程说明。 | |
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| === Assumptions made in this Article ===
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| === 文章假设 === | | === 文章假设 === |
| Generally, this article assumes you have a working knowledge of [[WordPress:Glossary#PHP|PHP]], [[WordPress:Glossary#MySQL|MySQL]], and WordPress capabilities.
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| 本文通常假设你拥有[[WordPress:Glossary#PHP|PHP]], [[WordPress:Glossary#MySQL|MySQL]]知识和WordPress 使用能力。 | | 本文通常假设你拥有[[WordPress:Glossary#PHP|PHP]], [[WordPress:Glossary#MySQL|MySQL]]知识和WordPress 使用能力。 |
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| Specific assumptions for the example, however, are:
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| 但此例的特定假设是: | | 但此例的特定假设是: |
| | *你至少拥有一篇[[WordPress:Using Custom Fields |定制区域]]数据文章。自定义区域有“标签”键和“电子邮件”键值。 |
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| * You have at least one post with [[WordPress:Using Custom Fields | Custom Fields]] data. The Custom Fields should have a key of 'tag' and a value of 'email' | | *你已创建一个[[WordPress:Pages|页面]]并有一个[[WordPress:Pages#Page_Templates|页面模板]]链接。在此例中,假定模板名称为'Qbased',它是从wp-content/themes/index.php模板复制的。如果你对此过程不熟悉,按照[[WordPress:Pages#Creating_your_own_Page_Templates|创建你自己的页面模板]]中的说明进行操作。 |
| *你至少拥有一篇[[WordPress:Using Custom Fields | Custom Fields]]数据文章。自定义字段有“标签”键和“电子邮件”键值。
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| * You have created a [[WordPress:Pages|Page]] and associated a [[WordPress:Pages#Page_Templates|Page Template]] with that page. For this example, assume the Template Name is 'Qbased' and was copied from the ''wp-content/themes/index.php'' template. If you are not familiar with this process, follow the instructions in [[WordPress:Pages#Creating_your_own_Page_Templates|Creating your own Page Templates]]. | | *由于这是稍先进的开发主题,推荐掌握[[WordPress:The Loop|循环]]的WordPress核心概念。 |
| *你已创建一个[[WordPress:Pages|Page]]并有一个[[WordPress:Pages#Page_Templates|Page Template]]链接。在此例中,假定模板名称为'Qbased',它是从wp-content/themes/index.php模板复制的。如果你对此过程不熟悉,按照[[WordPress:Pages#Creating_your_own_Page_Templates|Creating your own Page Templates]]中的说明进行操作。
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| * As this is a somewhat advanced developer topic, familiarity with the core WordPress concept of [[WordPress:The Loop]] is suggested.
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| *由于这是稍先进的开发主题,推荐掌握[[WordPress:The Loop]]的WordPress核心概念。
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| == Code for the Page Template ==
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| == 网页模板编码 == | | == 网页模板编码 == |
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| ===The query===
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| ===查询=== | | ===查询=== |
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| To begin with, it is necessary to retrieve the [[WordPress:Glossary#Recordset|recordset]] containing the posts you want to display. To do this, create a result set using the WordPress [[WordPress:Function_Reference/wpdb_Class|$wpdb database class]]. Note that the [[WordPress:Glossary#MySQL|MySQL]] [[WordPress:Wikipedia:SELECT|SELECT]] statement illustrates a '''simple''' [[WordPress:Wikipedia:JOIN|JOIN]]. Here, <tt>$pageposts</tt> will contain an [[WordPress:Glossary#Array|array]] of objects. Each object will represent a '''published''' post that has custom field key-value pair - with the key being 'tag' and the value being 'email':
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| 首先,需要检索[[WordPress:Glossary#Recordset|recordset]](数据集),里面包含你要显示的文章。要做到这一点,需要使用WordPress[[WordPress:Function_Reference/wpdb_Class|$wpdb database class]]创建一个result set(结果集)。注意[[WordPress:Glossary#MySQL|MySQL]] [[WordPress:Wikipedia:SELECT|SELECT]]指令阐明了一个“简单的” [[WordPress:Wikipedia:JOIN|JOIN]]。<tt>$pageposts</tt>在此会包含[[WordPress:Glossary#Array|array]]对象。每个对象代表一篇有自定义字段key-value(键-键值)配对且键名为tag,值为email的“已发布”文章。 | | 首先,需要检索[[WordPress:Glossary#Recordset|数据集],里面包含你要显示的文章。要做到这一点,需要使用WordPress[[WordPress:Function_Reference/wpdb_Class|$wpdb 数据库 类]]创建一个(结果集)。注意[[WordPress:Glossary#MySQL|MySQL]] [[WordPress:Wikipedia:SELECT|SELECT]]指令阐明了一个“简单的” [[WordPress:Wikipedia:JOIN|JOIN]]。<tt>$pageposts</tt>在此会包含[[WordPress:Glossary#Array|数组]]对象。每个对象代表一篇有自定义字段key-value(键-键值)配对且键名为tag,值为email的“已发布”文章。 |
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| <pre>
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| <?php
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| $querystr = "
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| SELECT wposts.*
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| FROM $wpdb->posts wposts, $wpdb->postmeta wpostmeta
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| WHERE wposts.ID = wpostmeta.post_id
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| AND wpostmeta.meta_key = 'tag'
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| AND wpostmeta.meta_value = 'email'
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| AND wposts.post_status = 'publish'
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| AND wposts.post_type = 'post'
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| ORDER BY wposts.post_date DESC
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| ";
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| $pageposts = $wpdb->get_results($querystr, OBJECT);
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| ?>
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| </pre>
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| <pre> | | <pre> |
| <?php | | <?php |
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| ===The Revised Loop===
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| ===已修改的Loop(循环)=== | | ===已修改的Loop(循环)=== |
| | | 现在,若要通过以前的[[WordPress:Wikipedia:SELECT|SELECT]] 标准来显示<tt>$pageposts</tt>中的文章,你需要用Qbased网页模板中你自己的循环编码来替代[[WordPress:The Loop]]。这需要创建一个已修改的循环(loop),使它能够循环<tt>$pageposts</tt>中的文章并显示它们。注意:下面loop(循环)中的结构/标记取自WordPress“默认”[[WordPress:Using Themes|主题]]. |
| Now, to display posts collected into <tt>$pageposts</tt> by the previous [[WordPress:Wikipedia:SELECT|SELECT]] criteria, you need to replace [[WordPress:The Loop]] with your own loop code in the ''Qbased'' Page Template. This requires creating a revised loop that cycles through the posts stored in <tt>$pageposts</tt> and displays them. Note: the structure / markup in the loop below is taken from the WordPress '''default''' [[WordPress:Using Themes|theme]].
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| 现在,若要通过以前的[[WordPress:Wikipedia:SELECT|SELECT]] 标准来显示<tt>$pageposts</tt>中的文章,你需要用Qbased网页模板中你自己的循环编码来替代[[WordPress:The Loop]]。这需要创建一个已修改的循环(loop),使它能够循环<tt>$pageposts</tt>中的文章并显示它们。注意:下面loop(循环)中的结构/标记取自WordPress“默认”[[WordPress:Using Themes|theme]]. | |
| 。 | | 。 |
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| <pre> | | <pre> |
| <?php if ($pageposts): ?> | | <?php if ($pageposts): ?> |
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| <?php endif; ?> | | <?php endif; ?> |
| </pre> | | </pre> |
| <pre>
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| <?php if ($pageposts): ?>
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| <?php foreach ($pageposts as $post): ?>
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| <?php setup_postdata($post); ?>
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| <div class="post" id="post-<?php the_ID(); ?>">
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| <h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>">
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| <?php the_title(); ?></a></h2>
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| <small><?php the_time('F jS, Y') ?> <!-- by <?php the_author() ?> --></small>
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| <div class="entry">
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| <?php the_content('Read the rest of this entry »'); ?>
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| </div>
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| <p class="postmetadata">Posted in <?php the_category(', ') ?> | <?php edit_post_link('Edit', '', ' | '); ?>
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| <?php comments_popup_link('No Comments »', '1 Comment »', '% Comments »'); ?></p>
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| </div>
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| <?php endforeach; ?>
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| <?php else : ?>
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| <h2 class="center">Not Found</h2>
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| <p class="center">Sorry, but you are looking for something that isn't here.</p>
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| <?php include (TEMPLATEPATH . "/searchform.php"); ?>
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| <?php endif; ?>
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| </pre>
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| And that's it!
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| 就是它! | | 就是它! |
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| To go through the important parts of the code, line by line, you have:
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| 一行一行地审查编码的重要部分,你必须: | | 一行一行地审查编码的重要部分,你必须: |
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| * A test to make sure that the query that populated <tt>$pageposts</tt> actually found some posts that matched the [[WordPress:Wikipedia:SELECT|SELECT]] criteria:
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| *测试以确保<tt>$pageposts</tt>中的查询可以查到符合[[WordPress:Wikipedia:SELECT|SELECT]]标准的文章: | | *测试以确保<tt>$pageposts</tt>中的查询可以查到符合[[WordPress:Wikipedia:SELECT|SELECT]]标准的文章: |
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| <?php if ($pageposts): ?> | | <?php if ($pageposts): ?> |
| </pre> | | </pre> |
| * A [[WordPress:Wikipedia:Foreach|foreach loop]] to go through the posts returned in <tt>$pageposts</tt> and display them:
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| <pre>
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| <?php foreach($pageposts as $post): ?>
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| </pre>
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| <pre>
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| <?php if ($pageposts): ?>
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| </pre>
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| * A [[WordPress:Wikipedia:Foreach|foreach loop]] to go through the posts returned in <tt>$pageposts</tt> and display them:
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| *[[WordPress:Wikipedia:Foreach|foreach loop]]审查已返回<tt>$pageposts</tt>的文章,并显示文章: | | *[[WordPress:Wikipedia:Foreach|foreach loop]]审查已返回<tt>$pageposts</tt>的文章,并显示文章: |
| <pre> | | <pre> |
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| </pre> | | </pre> |
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| * And, a call to the WordPress post formatting function, <tt>setup_postdata()</tt>, that automatically populates the required variables:
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| <pre>
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| <?php setup_postdata($post); ?>
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| </pre>
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| *调用WordPress文章格式化函数,<tt>setup_postdata()</tt>,自动填入所需变量: | | *调用WordPress文章格式化函数,<tt>setup_postdata()</tt>,自动填入所需变量: |
| <pre> | | <pre> |
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| ==== Within the Loop ====
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| ==== Loop (循环)内部==== | | ==== Loop (循环)内部==== |
| | 由于例子中调用了<tt>setup_postdata($post);</tt>,你可以使用可包括在正常Wordpress循环(loop)中的相同[[WordPress:Template Tags |模板标签]],如<tt>the_content()</tt> 和 <tt>the_permalink()</tt>。这意味着你能够较方便地用网页模板创建自己的文章显示结果,并自动利用你的Wordpress博客已激活的各种插件提供额外的格式和功能。 |
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| Because <tt>setup_postdata($post);</tt> was called in our example, you can use the same [[WordPress:Template Tags | template tags]] that can be included in a normal WordPress post loop, like <tt>the_content()</tt> and <tt>the_permalink()</tt>. This means that you can create your own post display results using a Page Template with a minimum amount of fuss, automatically taking advantage of the various plugins you may have activated in your WordPress blog to provide extra formatting and functionality.
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| 由于例子中调用了<tt>setup_postdata($post);</tt>,你可以使用可包括在正常Wordpress循环(loop)中的相同[[WordPress:Template Tags | template tags]],如<tt>the_content()</tt> 和 <tt>the_permalink()</tt>。这意味着你能够较方便地用网页模板创建自己的文章显示结果,并自动利用你的Wordpress博客已激活的各种插件提供额外的格式和功能。
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| === The Completed Page Template ===
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| ===已完成的网页模板=== | | ===已完成的网页模板=== |
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| Here is a complete example of the new template that works with the WordPress '''default''' theme.
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| 这是Wordpress“默认”主题运行的新模板的完整事例。 | | 这是Wordpress“默认”主题运行的新模板的完整事例。 |
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| <pre>
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| <?php
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| /*
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| Template Name: Qbased
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| */
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| ?>
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| <?php get_header(); ?>
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| <div id="content" class="narrowcolumn">
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| <?php
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| $querystr = "
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| SELECT wposts.*
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| FROM $wpdb->posts wposts, $wpdb->postmeta wpostmeta
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| WHERE wposts.ID = wpostmeta.post_id
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| AND wpostmeta.meta_key = 'tag'
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| AND wpostmeta.meta_value = 'email'
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| AND wposts.post_status = 'publish'
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| AND wposts.post_type = 'post'
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| AND wposts.post_date < NOW()
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| ORDER BY wposts.post_date DESC
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| ";
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|
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| $pageposts = $wpdb->get_results($querystr, OBJECT);
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|
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| ?>
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| <?php if ($pageposts): ?>
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| <?php foreach ($pageposts as $post): ?>
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| <?php setup_postdata($post); ?>
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|
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| <div class="post" id="post-<?php the_ID(); ?>">
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| <h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>">
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| <?php the_title(); ?></a></h2>
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| <small><?php the_time('F jS, Y') ?> <!-- by <?php the_author() ?> --></small>
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| <div class="entry">
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| <?php the_content('Read the rest of this entry »'); ?>
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| </div>
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| <p class="postmetadata">Posted in <?php the_category(', ') ?> | <?php edit_post_link('Edit', '', ' | '); ?>
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| <?php comments_popup_link('No Comments »', '1 Comment »', '% Comments »'); ?></p>
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| </div>
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| <?php endforeach; ?>
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|
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| <?php else : ?>
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| <h2 class="center">Not Found</h2>
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| <p class="center">Sorry, but you are looking for something that isn't here.</p>
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| <?php include (TEMPLATEPATH . "/searchform.php"); ?>
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| <?php endif; ?>
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|
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| </div>
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|
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| <?php get_sidebar(); ?>
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|
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| <?php get_footer(); ?>
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| </pre>
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| <pre> | | <pre> |
| <?php | | <?php |
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| </pre> | | </pre> |
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| It is important to note here that the above example will work '''only''' when OBJECT is passed as the "output_type" parameter for <code>$wpdb->get_results()</code>. setup_postdata() does not seem to work when ARRAY_A or ARRAY_N is passed in $wpdb->get_results().
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| 这里值得注意的是,上述例子“只有”当<code>$wpdb->get_results()</code>是以"output_type"为参数,面向对象通过时才运行。当ARRAY_A 或ARRAY_N在$wpdb->get_results()通过时,setup_postdata()似乎不运行。 | | 这里值得注意的是,上述例子“只有”当<code>$wpdb->get_results()</code>是以"output_type"为参数,面向对象通过时才运行。当ARRAY_A 或ARRAY_N在$wpdb->get_results()通过时,setup_postdata()似乎不运行。 |
| | | ==定制区域和类别基础上的查询== |
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| ==Query based on Custom Field and Category== | |
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| ==自定义字段和类别基础上的查询==
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| This next example sets the $querystr variable used in the above example, to get all posts in Categories 1,2, and 3, that have the meta_key 'paragraf', and then sorted ascending by the meta_values. This example gleaned from Otto42's response in [http://wordpress.org/support/topic/121011 Forum Topic 121011].
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| 此事例设置了上个事例中使用的$querystr变量以获得类别1,2,和3中的有meta_key 'paragraf'的所有文章,并按meta_values升序排列。此例来源于Otto42在[http://wordpress.org/support/topic/121011 Forum Topic 121011]. | | 此事例设置了上个事例中使用的$querystr变量以获得类别1,2,和3中的有meta_key 'paragraf'的所有文章,并按meta_values升序排列。此例来源于Otto42在[http://wordpress.org/support/topic/121011 Forum Topic 121011]. |
| 中的回复。 | | 中的回复。 |
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| <pre>
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| $querystr = "
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| SELECT $wpdb->posts.*
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| FROM $wpdb->posts
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| LEFT JOIN $wpdb->postmeta ON ($wpdb->posts.ID = $wpdb->postmeta.post_id)
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| LEFT JOIN $wpdb->post2cat ON ($wpdb->posts.ID = $wpdb->post2cat.post_id)
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| WHERE $wpdb->postmeta.meta_key = 'paragraf'
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| AND $wpdb->posts.post_status = 'publish'
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| AND $wpdb->posts.post_type = 'post'
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| AND $wpdb->post2cat.category_id IN (1,2,3)
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| ORDER BY $wpdb->postmeta.meta_value ASC
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| ";
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|
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| </pre>
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|
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| <pre> | | <pre> |
| $querystr = " | | $querystr = " |
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| </pre> | | </pre> |
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| '''with wordpress 2.3 you need to update the sql query shown above to this:'''
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| This example gleaned from kernow's response in [http://wordpress.org/support/topic/121011 Forum Topic 121011]
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| '''使用 wordpress2.3,你需要把以上显示的sql查询更新为:''' | | '''使用 wordpress2.3,你需要把以上显示的sql查询更新为:''' |
| 此例来源于kernow在[http://wordpress.org/support/topic/121011 Forum Topic 121011] 中的回复 | | 此例来源于kernow在[http://wordpress.org/support/topic/121011 Forum Topic 121011] 中的回复 |
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| <pre> | | <pre> |
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| ORDER BY $wpdb->postmeta.meta_value ASC | | ORDER BY $wpdb->postmeta.meta_value ASC |
| </pre> | | </pre> |
| <pre>
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| SELECT * FROM $wpdb->posts
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| LEFT JOIN $wpdb->postmeta ON($wpdb->posts.ID = $wpdb->postmeta.post_id)
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| LEFT JOIN $wpdb->term_relationships ON($wpdb->posts.ID = $wpdb->term_relationships.object_id)
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| LEFT JOIN $wpdb->term_taxonomy ON($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id)
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| WHERE $wpdb->term_taxonomy.term_id = 1,2,3
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| AND $wpdb->term_taxonomy.taxonomy = 'category'
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| AND $wpdb->posts.post_status = 'publish'
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| AND $wpdb->postmeta.meta_key = 'paragraf'
| |
| ORDER BY $wpdb->postmeta.meta_value ASC
| |
| </pre>
| |
|
| |
| == Acknowledgements ==
| |
| ==致谢 == | | ==致谢 == |
|
| |
| Many thanks to [http://wordpress.org/support/profile/6445 Kafkaesquii] for pointing out a simpler method of populating the appropriate global variables, etc, using setup_postdata().
| |
| 非常感谢[http://wordpress.org/support/profile/6445 Kafkaesquii]指出填写适当全局变量等的更简便方法:使用setup_postdata()。 | | 非常感谢[http://wordpress.org/support/profile/6445 Kafkaesquii]指出填写适当全局变量等的更简便方法:使用setup_postdata()。 |
描述[ ]
在你的WordPress发展历程的某个时刻,或许你需要通过非WordPress的 query_posts 架构提供的选择标准来显示一篇或更多的文章。例如,你有时或许必须加入 WordPress表格以确定要显示的文章或使用自己表格中的储存数据来确定要显示正在写的文章。
以下概述的实例展示了这样一个过程:选择有 定制区域存入值的所有文章并把它们在建立在页面模板基础上的页面显示出来。这些编码最初用来执行文章标签插件,它允许以比WordPress分类稍无序的构架来组织文章。你的使用或许有所不同,但以下的例子仍会给你提供些有用的一般过程说明。
文章假设[ ]
本文通常假设你拥有PHP, MySQL知识和WordPress 使用能力。
但此例的特定假设是:
- 你至少拥有一篇定制区域数据文章。自定义区域有“标签”键和“电子邮件”键值。
- 你已创建一个页面并有一个页面模板链接。在此例中,假定模板名称为'Qbased',它是从wp-content/themes/index.php模板复制的。如果你对此过程不熟悉,按照创建你自己的页面模板中的说明进行操作。
- 由于这是稍先进的开发主题,推荐掌握循环的WordPress核心概念。
网页模板编码[ ]
查询[ ]
首先,需要检索[[WordPress:Glossary#Recordset|数据集],里面包含你要显示的文章。要做到这一点,需要使用WordPress$wpdb 数据库 类创建一个(结果集)。注意MySQL SELECT指令阐明了一个“简单的” JOIN。$pageposts在此会包含数组对象。每个对象代表一篇有自定义字段key-value(键-键值)配对且键名为tag,值为email的“已发布”文章。
<?php
$querystr = "
SELECT wposts.*
FROM $wpdb->posts wposts, $wpdb->postmeta wpostmeta
WHERE wposts.ID = wpostmeta.post_id
AND wpostmeta.meta_key = 'tag'
AND wpostmeta.meta_value = 'email'
AND wposts.post_status = 'publish'
AND wposts.post_type = 'post'
ORDER BY wposts.post_date DESC
";
$pageposts = $wpdb->get_results($querystr, OBJECT);
?>
已修改的Loop(循环)[ ]
现在,若要通过以前的SELECT 标准来显示$pageposts中的文章,你需要用Qbased网页模板中你自己的循环编码来替代WordPress:The Loop。这需要创建一个已修改的循环(loop),使它能够循环$pageposts中的文章并显示它们。注意:下面loop(循环)中的结构/标记取自WordPress“默认”主题.
。
<?php if ($pageposts): ?>
<?php foreach ($pageposts as $post): ?>
<?php setup_postdata($post); ?>
<div class="post" id="post-<?php the_ID(); ?>">
<h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>">
<?php the_title(); ?></a></h2>
<small><?php the_time('F jS, Y') ?> <!-- by <?php the_author() ?> --></small>
<div class="entry">
<?php the_content('Read the rest of this entry »'); ?>
</div>
<p class="postmetadata">Posted in <?php the_category(', ') ?> | <?php edit_post_link('Edit', '', ' | '); ?>
<?php comments_popup_link('No Comments »', '1 Comment »', '% Comments »'); ?></p>
</div>
<?php endforeach; ?>
<?php else : ?>
<h2 class="center">Not Found</h2>
<p class="center">Sorry, but you are looking for something that isn't here.</p>
<?php include (TEMPLATEPATH . "/searchform.php"); ?>
<?php endif; ?>
就是它!
一行一行地审查编码的重要部分,你必须:
- 测试以确保$pageposts中的查询可以查到符合SELECT标准的文章:
<?php if ($pageposts): ?>
<?php foreach($pageposts as $post): ?>
- 调用WordPress文章格式化函数,setup_postdata(),自动填入所需变量:
<?php setup_postdata($post); ?>
Loop (循环)内部[ ]
由于例子中调用了setup_postdata($post);,你可以使用可包括在正常Wordpress循环(loop)中的相同模板标签,如the_content() 和 the_permalink()。这意味着你能够较方便地用网页模板创建自己的文章显示结果,并自动利用你的Wordpress博客已激活的各种插件提供额外的格式和功能。
已完成的网页模板[ ]
这是Wordpress“默认”主题运行的新模板的完整事例。
<?php
/*
Template Name: Qbased
*/
?>
<?php get_header(); ?>
<div id="content" class="narrowcolumn">
<?php
$querystr = "
SELECT wposts.*
FROM $wpdb->posts wposts, $wpdb->postmeta wpostmeta
WHERE wposts.ID = wpostmeta.post_id
AND wpostmeta.meta_key = 'tag'
AND wpostmeta.meta_value = 'email'
AND wposts.post_status = 'publish'
AND wposts.post_type = 'post'
AND wposts.post_date < NOW()
ORDER BY wposts.post_date DESC
";
$pageposts = $wpdb->get_results($querystr, OBJECT);
?>
<?php if ($pageposts): ?>
<?php foreach ($pageposts as $post): ?>
<?php setup_postdata($post); ?>
<div class="post" id="post-<?php the_ID(); ?>">
<h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>">
<?php the_title(); ?></a></h2>
<small><?php the_time('F jS, Y') ?> <!-- by <?php the_author() ?> --></small>
<div class="entry">
<?php the_content('Read the rest of this entry »'); ?>
</div>
<p class="postmetadata">Posted in <?php the_category(', ') ?> | <?php edit_post_link('Edit', '', ' | '); ?>
<?php comments_popup_link('No Comments »', '1 Comment »', '% Comments »'); ?></p>
</div>
<?php endforeach; ?>
<?php else : ?>
<h2 class="center">Not Found</h2>
<p class="center">Sorry, but you are looking for something that isn't here.</p>
<?php include (TEMPLATEPATH . "/searchform.php"); ?>
<?php endif; ?>
</div>
<?php get_sidebar(); ?>
<?php get_footer(); ?>
这里值得注意的是,上述例子“只有”当$wpdb->get_results()
是以"output_type"为参数,面向对象通过时才运行。当ARRAY_A 或ARRAY_N在$wpdb->get_results()通过时,setup_postdata()似乎不运行。
定制区域和类别基础上的查询[ ]
此事例设置了上个事例中使用的$querystr变量以获得类别1,2,和3中的有meta_key 'paragraf'的所有文章,并按meta_values升序排列。此例来源于Otto42在Forum Topic 121011.
中的回复。
$querystr = "
SELECT $wpdb->posts.*
FROM $wpdb->posts
LEFT JOIN $wpdb->postmeta ON ($wpdb->posts.ID = $wpdb->postmeta.post_id)
LEFT JOIN $wpdb->post2cat ON ($wpdb->posts.ID = $wpdb->post2cat.post_id)
WHERE $wpdb->postmeta.meta_key = 'paragraf'
AND $wpdb->posts.post_status = 'publish'
AND $wpdb->posts.post_type = 'post'
AND $wpdb->post2cat.category_id IN (1,2,3)
ORDER BY $wpdb->postmeta.meta_value ASC
";
使用 wordpress2.3,你需要把以上显示的sql查询更新为:
此例来源于kernow在Forum Topic 121011 中的回复
SELECT * FROM $wpdb->posts
LEFT JOIN $wpdb->postmeta ON($wpdb->posts.ID = $wpdb->postmeta.post_id)
LEFT JOIN $wpdb->term_relationships ON($wpdb->posts.ID = $wpdb->term_relationships.object_id)
LEFT JOIN $wpdb->term_taxonomy ON($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id)
WHERE $wpdb->term_taxonomy.term_id = 1,2,3
AND $wpdb->term_taxonomy.taxonomy = 'category'
AND $wpdb->posts.post_status = 'publish'
AND $wpdb->postmeta.meta_key = 'paragraf'
ORDER BY $wpdb->postmeta.meta_value ASC
致谢[ ]
非常感谢Kafkaesquii指出填写适当全局变量等的更简便方法:使用setup_postdata()。