functions.php
/* 前後リンクを生成(長いタイトルを丸める)
============================================= */
function Custom_previous_post_link($maxlen = -1, $format='« %link', $link='%title', $in_same_cat = false, $excluded_categories = '') {
Custom_adjacent_post_link($maxlen, $format, $link, $in_same_cat, $excluded_categories, true, $maxlen);
}
function Custom_next_post_link($maxlen = -1, $format='%link »', $link='%title', $in_same_cat = false, $excluded_categories = '') {
Custom_adjacent_post_link($maxlen, $format, $link, $in_same_cat, $excluded_categories, false);
}
function Custom_adjacent_post_link($maxlen = -1, $format='« %link', $link='%title', $in_same_cat = false, $excluded_categories = '', $previous = true) {
if ( $previous && is_attachment() )
$post = & get_post($GLOBALS['post']->post_parent);
else
$post = get_adjacent_post($in_same_cat, $excluded_categories, $previous);
if ( !$post )
return;
$tCnt = mb_strlen( $post->post_title, get_bloginfo('charset') );
if(($maxlen > 0)&&($tCnt > $maxlen)) {
$title = mb_substr( $post->post_title, 0, $maxlen, get_bloginfo('charset') ) . '…';
} else {
$title = $post->post_title;
}
if ( empty($post->post_title) )
$title = $previous ? __('Previous Post') : __('Next Post');
$title = apply_filters('the_title', $title, $post->ID);
$date = mysql2date(get_option('date_format'), $post->post_date);
$rel = $previous ? 'prev' : 'next';
$string = '<a href="'.get_permalink($post).'" rel="'.$rel.'">';
$link = str_replace('%title', $title, $link);
$link = str_replace('%date', $date, $link);
$link = $string . $link . '</a>';
$format = str_replace('%link', $link, $format);
echo $format;
}
で該当するprevious(next)_post_link()を探してきて、下記のように変更
//タイトルを丸める場合
<?php Custom_previous_post_link(15) ?>
<?php Custom_next_post_link(15) ?>
//フォーマットなどをすべてのオプションを指定する場合
<?php Custom_previous_post_link(12, '%link', '« %title', true) ?>
<?php Custom_next_post_link(12, '%link', '« %title', true) ?>
最初の引数を丸める文字数を指定して、その後の引数は、previous post linkのオプションと同じように指定する。