我有一个显示书籍信息的网站。

我想添加Schema.org 包含书籍的帖子的微数据标记。

我使用名为WP Types 因此，我可以在这些字段中添加所需的标记值。

然后，我创建了一个函数来显示single.php.

我的问题是，并非每本书都有相同数量的微观数据。（例如，有些书没有翻译，所以他们没有翻译）。这会导致糟糕的结果，因为帖子将显示包含大量未填充数据的表格。

我想修改该函数以表示以下逻辑：

if this custom field has value, echo this row

然后，我可以将此修改应用于每一行，因此最终结果将是每个帖子的一个有意义的表，其中只包含可用数据。

有没有办法在我的代码中应用上述逻辑？

以下是我创建的代码：

/* Schema.Org Book Microdata For Books Page Template */
function add_schema_book_microdata () {
if ( in_category(\'downloads\') ) {
echo \'<div class="schema_book_microdata_container">\';
            echo \'<div itemscope itemtype="http://schema.org/Book">\'; 
                echo \'<h3>\'; echo \'Book Identification Card\'; echo \'</h3>\';
                echo \'<table class="schema_book_microdata_table">\';
                    echo \'<tr>\';
                        echo \'<th class="schema-book-table-initial-column">\'; echo \'Data\'; echo \'</th>\';
                        echo \'<th>\';echo \'Details\'; echo \'</th>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Author\'; echo \'</td>\';
                        echo \'<td>\';  
                            echo \'<span itemprop="author" itemscope itemtype="http://schema.org/Person">\';
                            echo\'<span itemprop="honorificPrefix">\'; echo types_render_field("schema-book-author-honorific-prefix", array( ) ); echo\' </span>\';
                            echo\'<span itemprop="givenName">\'; echo types_render_field( "schema-book-author-given-name", array( ) ); echo\' </span>\';
                            echo\'<span itemprop="familyName">\'; echo types_render_field("schema-book-author-family-name", array( ) ); echo\' </span>\'; 
                            echo\'<span itemprop="honorificSuffix">\'; echo types_render_field("schema-book-author-honorific-suffix", array( ) ); echo\' </span>\';
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Author Job Title\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="author" itemscope itemtype="http://schema.org/Person">\';
                            echo\'<span itemprop="jobTitle">\'; echo types_render_field("schema-book-author-job-title", array( ) ); echo\'</span>\';      
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Other Names for Author\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="author" itemscope itemtype="http://schema.org/Person">\';
                            echo\'<span itemprop="additionalName">\'; echo types_render_field("schema-book-author-additional-name", array( ) ); echo\'</span>\';      
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Translator\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="translator" itemscope itemtype="http://schema.org/Person">\';
                            echo\'<span itemprop="honorificPrefix">\'; echo types_render_field("schema-book-translator-honorific-prefix", array( ) ); echo\' </span>\';
                            echo\'<span itemprop="givenName">\'; echo types_render_field( "schema-book-translator-given-name", array( ) ); echo\' </span>\';
                            echo\'<span itemprop="familyName">\'; echo types_render_field("schema-book-translator-family-name", array( ) ); echo\' </span>\'; 
                            echo\'<span itemprop="honorificSuffix">\'; echo types_render_field("schema-book-translator-honorific-suffix", array( ) ); echo\' </span>\';
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Translation Organization\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="translator" itemscope itemtype="http://schema.org/Organization">\';
                            echo\'<span itemprop="name">\'; echo types_render_field( "schema-book-translator-organization", array( ) ); echo\'</span>\';      
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';

                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Editor\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="editor" itemscope itemtype="http://schema.org/Person">\';
                            echo\'<span itemprop="honorificPrefix">\'; echo types_render_field("schema-book-editor-honorific-prefix", array( ) ); echo\' </span>\';
                            echo\'<span itemprop="givenName">\'; echo types_render_field( "schema-book-editor-given-name", array( ) ); echo\' </span>\';
                            echo\'<span itemprop="familyName">\'; echo types_render_field("schema-book-editor-family-name", array( ) ); echo\' </span>\'; 
                            echo\'<span itemprop="honorificSuffix">\'; echo types_render_field("schema-book-editor-honorific-suffix", array( ) ); echo\' </span>\';
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Publisher\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="publisher" itemscope itemtype="http://schema.org/Organization">\';
                            echo\'<span itemprop="name">\'; echo types_render_field( "schema-book-publisher", array( ) ); echo\'</span>\';    
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Edition\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="bookEdition">\'; echo types_render_field("schema-book-edition", array( ) ); 
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'No. of Pages\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="numberOfPages">\'; echo types_render_field("schema-book-number-of-pages", array( ) ); 
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'Date Published\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="datePublished">\'; echo types_render_field("schema-book-publish-date", array( ) ); 
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                    echo \'<tr>\';
                        echo \'<td>\'; echo\'ISBN/ISSN\'; echo \'</td>\';
                        echo \'<td>\';
                            echo \'<span itemprop="isbn">\'; echo types_render_field("schema-book-isbn-issn", array( ) ); 
                            echo \'</span>\';
                        echo \'</td>\';
                    echo \'</tr>\';
                echo \'</table>\';
    echo \'</div>\';

    }
}

$author_info = array_filter( array (
    \'honorificPrefix\' => types_render_field( "schema-book-author-honorific-prefix", array () ),
    \'givenName\'       => types_render_field( "schema-book-author-given-name", array () ),
    \'familyName\'      => types_render_field( "schema-book-author-family-name", array () ),
    \'honorificSuffix\' => types_render_field( "schema-book-author-honorific-suffix", array () ),
) );

if ( ! empty( $author_info ) ) {

    echo \'<tr><td>Author</td><td><span itemprop="author" itemscope itemtype="http://schema.org/Person">\';

    foreach ( $author_info as $prop => $value ) {

        printf( \'<span itemprop="%s">%s</span>\', $prop, $value );

    }

    echo \'</span></td></tr>\';
}