下面的代码将首先打印出所有顶级类别，然后打印出所有非顶级类别，如果这是您想要的。

<?php 
$categories = get_the_category( get_the_ID() );
if( $categories ){
    $output = "";

    //display all the top-level categories first
    foreach ($categories as $category) {
        if( !$category->parent ){
            $output .= \'<a href="\' . esc_url( get_category_link( $category->term_id ) ) . \'" title="\' . esc_attr( sprintf( __( "View all posts in %s" ), $category->name ) ) . \'" >\' . $category->name.\'</a>,\';
        }
    }

    //now, display all the child categories
    foreach ($categories as $category) {
        if( $category->parent ){
            $output .= \'<a href="\' . esc_url( get_category_link( $category->term_id ) ) . \'" title="\' . esc_attr( sprintf( __( "View all posts in %s" ), $category->name ) ) . \'" >\' . $category->name.\'</a>,\';
        }
    }

    echo trim( $output, "," );
}
?>