我想用类别填充数组，并试图用in\\u数组防止重复：
if ( $query->have_posts() ) {
$categories = array();
while ( $query->have_posts() ) {
$query->the_post();
foreach((get_the_category()) as $category) {
if(!in_array($category, $categories)) {
$categories[] = $category;
}
}
};
} ?>
可以这样尝试：
if ( $query->have_posts() ) {
$categories = $category_ids = array();
while ( $query->have_posts() ) {
$query->the_post();
foreach ( ( get_the_category() ) as $category ) {
if ( ! in_array( $category->term_id, $category_ids ) ) {
$category_ids[] = $category->term_id;
$categories[] = $category;
}
}
};
}
get_the_category() 返回对象数组。我没有检查in_array 文档，但我怀疑它不包括对象匹配。$category_ids 是仅用于比较的ID的数组。您好，我收到Wordpress includes的一个错误，当我发布分类法的多个值时会出现此错误<form role=\"search\" method=\"post\" id=\"searchform\" action=\"<?php echo home_url( \'/\' ); ?>\"> <select name=\"books[]\" multiple> <option value=\"a\">a</option