$ GLOBALS ['wp_the_query']与全局$ wp_query

您错过了一个$GLOBALS['wp_query'].为了所有目的,$GLOBALS['wp_query'] === $wp_query.但是,$GLOBALS['wp_query']可读性更好,应该代替$wp_query(但仍会保留个人喜好)

现在,在一个由独角兽统治世界的理想世界中,$GLOBALS['wp_the_query'] === $GLOBALS['wp_query'] === $wp_query.默认情况下,这应该是正确的.如果我们看看这些全局变量的设置位置( wp-settings.php ),您将看到主查询对象存储在$GLOBALS['wp_the_query']中,$GLOBALS['wp_query']只是$GLOBALS['wp_the_query']

 /**
 * WordPress Query object
 * @global WP_Query $wp_the_query
 * @since 2.0.0
 */
$GLOBALS['wp_the_query'] = new WP_Query();
/**
 * Holds the reference to @see $wp_the_query
 * Use this global for WordPress queries
 * @global WP_Query $wp_query
 * @since 1.5.0
 */
$GLOBALS['wp_query'] = $GLOBALS['wp_the_query'];
 

之所以这样做,是因为WordPress看到了 query_posts .

 function query_posts($query) {
    $GLOBALS['wp_query'] = new WP_Query();
    return $GLOBALS['wp_query']->query($query);
}
 

如您所见,query_posts将主查询对象设置为当前的自定义查询开始运行.这会破坏主查询对象的完整性,从而为您提供不正确的数据,因此依赖主查询对象的所有内容都会由于数据错误而损坏.

解决此问题的一种方法是创建另一个全局变量来存储主要查询对象$GLOBALS['wp_the_query'],此版本在2.0.0版本中引入.这个新的全局保存主查询对象,而$GLOBALS['wp_query']只是一个副本.通过wp_reset_query(),我们现在可以将$GLOBALS['wp_query']重置回原始主查询对象,以恢复其完整性.

但这不是一个完美的世界,query_posts本身就是魔鬼.尽管有成千上万的警告,但人们仍然使用query_posts.除了中断主查询之外,它还会重新运行主查询,这使得它与WP_Query的常规自定义查询相比要慢得多.完成后,许多人也不会使用wp_reset_query()重置query_posts查询,这使query_posts更加邪恶.

因为我们对此无能为力,也无法停止使用query_posts的插件和主题,并且我们永远无法知道query_posts查询是否已通过wp_reset_query(),我们需要主查询对象的更可靠副本,我们知道它将为我们提供99.99999％可靠,正确的数据.这就是$GLOBALS['wp_the_query']有用的地方,因为没有WordPress相关代码可以更改其值(除外,通过WP_Query本身内部的过滤器和操作).

快速证明,运行以下

 var_dump( $GLOBALS['wp_the_query'] );
var_dump( $GLOBALS['wp_query'] );

query_posts( 's=crap' );


var_dump( $GLOBALS['wp_the_query'] );
var_dump( $GLOBALS['wp_query'] );
 

,然后检查结果. $GLOBALS['wp_the_query']不变,而$GLOBALS['wp_query']不变.那么哪个更可靠?

最后的注释,$GLOBALS['wp_the_query'] 不代替wp_reset_query(). wp_reset_query()应该始终与query_posts一起使用,而query_posts应该从不用过的.

结论

如果您需要可靠的代码(几乎永远不会失败),请使用$GLOBALS['wp_the_query'],如果您相信并相信插件和主题代码并且认为没有人使用query_posts或使用正确,请使用$GLOBALS['wp_query']或$wp_query

重要编辑

现在在这个网站上回答问题已有两年了,我看到许多用户使用$wp_query作为局部变量,这反过来又破坏了主查询对象.这进一步增加了$wp_query的漏洞.

例如,有人对此

 $wp_query = new WP_Query( $args );
 

从本质上讲与query_posts正在执行的操作完全相同

You have missed one, $GLOBALS['wp_query']. For all purposes, $GLOBALS['wp_query'] === $wp_query. $GLOBALS['wp_query'] is however better for readability and should be used instead of $wp_query, BUT, that remains personal preference

Now, in a perfect world where unicorns rule the world, $GLOBALS['wp_the_query'] === $GLOBALS['wp_query'] === $wp_query. By default, this should be true. If we look at where these globals are set (wp-settings.php), you will see the main query object is stored in $GLOBALS['wp_the_query'] and $GLOBALS['wp_query'] is just a duplicate copy of $GLOBALS['wp_the_query']

/**
 * WordPress Query object
 * @global WP_Query $wp_the_query
 * @since 2.0.0
 */
$GLOBALS['wp_the_query'] = new WP_Query();
/**
 * Holds the reference to @see $wp_the_query
 * Use this global for WordPress queries
 * @global WP_Query $wp_query
 * @since 1.5.0
 */
$GLOBALS['wp_query'] = $GLOBALS['wp_the_query'];

The reason for doing it this way, is because WordPress saw the arrival of query_posts in version 1.5.

function query_posts($query) {
    $GLOBALS['wp_query'] = new WP_Query();
    return $GLOBALS['wp_query']->query($query);
}

As you can see, query_posts sets the main query object to the current custom query beign run. This breaks the integrity of the main query object, which gives you incorrect data, so anything that relies on the main query object is broken due to wrong data.

A way to counter this was to create another global to store the main query object, $GLOBALS['wp_the_query'] which was introduced in version 2.0.0. This new global hold the main query object and $GLOBALS['wp_query'] just a copy. Through wp_reset_query(), we could now reset $GLOBALS['wp_query'] back to the original main query object to restore its integrity.

But this is not a perfect world, and query_posts are the devil himself. Although thousands of warnings, people still use query_posts. Apart from breaking the main query, it reruns the main query, making it much slower as a normal custom query with WP_Query. Many people also do not reset the query_posts query with wp_reset_query() when done, which makes query_posts even more evil.

Because we cannot do anything about that, and cannot stop plugins and themes from using query_posts and we can never know if a query_posts query was reset with wp_reset_query(), we need a more reliable copy of the main query object which we know will give us 99.99999% reliable, correct data. That is where $GLOBALS['wp_the_query'] is useful as no WordPress related code can change it's value (except through the filters and actions inside WP_Query itself).

Quick proof, run the following

var_dump( $GLOBALS['wp_the_query'] );
var_dump( $GLOBALS['wp_query'] );

query_posts( 's=crap' );


var_dump( $GLOBALS['wp_the_query'] );
var_dump( $GLOBALS['wp_query'] );

and check the results. $GLOBALS['wp_the_query'] did not change, and $GLOBALS['wp_query'] has. So which is more reliable?

Final note, $GLOBALS['wp_the_query'] is NOT a replacement for wp_reset_query(). wp_reset_query() should always be used with query_posts, and query_posts should never be used.

TO CONCLUDE

If you need reliable code which will almost always never fail, use $GLOBALS['wp_the_query'], if you trust and believe plugins and theme code and believe no one uses query_posts or is using it correctly, use $GLOBALS['wp_query'] or $wp_query

IMPORTANT EDIT

Being answering questions on this site now for a couple of years, I saw many users using $wp_query as a local variable, which in turn also breaks the main query object. This further increases the vulnerabilty of the $wp_query.

As example, some people to this

$wp_query = new WP_Query( $args );

which is in essence the exactly the same as what query_posts are doing

global关键字将变量导入本地范围,而$ GLOBALS仅授予您访问变量的权限.

详细说明一下,如果您使用global $wp_the_query; 您可以在本地范围内使用$wp_the_query,而无需再次使用global.因此,基本上可以将global $wp_the_query与$wp_the_query = $GLOBALS['wp_the_query']

编辑

我将wp_query误读为wp_the_query,因此我的答案不是问题的完整答案,但仍提供有关global $variable和$GLOBALS['variable']

The global keyword imports the variable into the local scope, while $GLOBALS just grants you access to the variable.

To elaborate, if you use global $wp_the_query; you can use $wp_the_query inside the local scope without using the word global again. So basically global $wp_the_query can be compared to $wp_the_query = $GLOBALS['wp_the_query']

EDIT

I misread wp_query for wp_the_query so my answer isn't a complete answer to the question but still provides general information about the difference between global $variable and $GLOBALS['variable']

基本上一个是另一个的副本.查看 wp-settings.php ,第292-305行:

 $GLOBALS['wp_the_query'] = new WP_Query();

$GLOBALS['wp_query'] = $GLOBALS['wp_the_query'];
 

Basically one is copy of the other. Check out wp-settings.php, lines 292-305:

$GLOBALS['wp_the_query'] = new WP_Query();

$GLOBALS['wp_query'] = $GLOBALS['wp_the_query'];