get_the_content

get_the_content: 這個函式檢索當前文章或頁面的主要內容。它需要兩個可選引數：更多的連結文字和是否只顯示更多標籤之前的內容部分。它以字串形式返回內容。

檢索文章的內容。

function get_the_content( $more_link_text = null, $strip_teaser = false, $post = null ) {
	global $page, $more, $preview, $pages, $multipage;

	$_post = get_post( $post );

	if ( ! ( $_post instanceof WP_Post ) ) {
		return '';
	}

	// Use the globals if the $post parameter was not specified,
	// but only after they have been set up in setup_postdata().
	if ( null === $post && did_action( 'the_post' ) ) {
		$elements = compact( 'page', 'more', 'preview', 'pages', 'multipage' );
	} else {
		$elements = generate_postdata( $_post );
	}

	if ( null === $more_link_text ) {
		$more_link_text = sprintf(
			'<span aria-label="%1$s">%2$s</span>',
			sprintf(
				/* translators: %s: Post title. */
				__( 'Continue reading %s' ),
				the_title_attribute(
					array(
						'echo' => false,
						'post' => $_post,
					)
				)
			),
			__( '(more&hellip;)' )
		);
	}

	$output     = '';
	$has_teaser = false;

	// If post password required and it doesn't match the cookie.
	if ( post_password_required( $_post ) ) {
		return get_the_password_form( $_post );
	}

	// If the requested page doesn't exist.
	if ( $elements['page'] > count( $elements['pages'] ) ) {
		// Give them the highest numbered page that DOES exist.
		$elements['page'] = count( $elements['pages'] );
	}

	$page_no = $elements['page'];
	$content = $elements['pages'][ $page_no - 1 ];
	if ( preg_match( '/<!--more(.*?)?-->/', $content, $matches ) ) {
		if ( has_block( 'more', $content ) ) {
			// Remove the core/more block delimiters. They will be left over after $content is split up.
			$content = preg_replace( '/<!-- /?wp:more(.*?) -->/', '', $content );
		}

		$content = explode( $matches[0], $content, 2 );

		if ( ! empty( $matches[1] ) && ! empty( $more_link_text ) ) {
			$more_link_text = strip_tags( wp_kses_no_null( trim( $matches[1] ) ) );
		}

		$has_teaser = true;
	} else {
		$content = array( $content );
	}

	if ( false !== strpos( $_post->post_content, '<!--noteaser-->' ) && ( ! $elements['multipage'] || 1 == $elements['page'] ) ) {
		$strip_teaser = true;
	}

	$teaser = $content[0];

	if ( $elements['more'] && $strip_teaser && $has_teaser ) {
		$teaser = '';
	}

	$output .= $teaser;

	if ( count( $content ) > 1 ) {
		if ( $elements['more'] ) {
			$output .= '<span id="more-' . $_post->ID . '"></span>' . $content[1];
		} else {
			if ( ! empty( $more_link_text ) ) {

				/**
				 * Filters the Read More link text.
				 *
				 * @since 2.8.0
				 *
				 * @param string $more_link_element Read More link element.
				 * @param string $more_link_text    Read More text.
				 */
				$output .= apply_filters( 'the_content_more_link', ' <a href="' . get_permalink( $_post ) . "#more-{$_post->ID}" class="more-link">$more_link_text</a>", $more_link_text );
			}
			$output = force_balance_tags( $output );
		}
	}

	return $output;
}