截断字符串的选项

方法 #1：简单

function myTruncate($string, $limit, $break=".", $pad="...") {
        if(strlen($string) <= $limit) return $string; 
        if(false !== ($breakpoint = strpos($string, $break, $limit))) { 
            if($breakpoint < strlen($string) - 1) { 
                $string = substr($string, 0, $breakpoint) . $pad; } 
            } return $string; 
}

方法 #2：简单

function ellipsis($text, $max=100, $append='…') {
       if (strlen($text) <= $max) return $text;
       $out = substr($text,0,$max);
       if (strpos($text,' ') === FALSE) return $out.$append;
       return preg_replace('/\w+$/','',$out).$append;
}

用法

<?php
$text = "Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo.";
echo ellipsis($text,100);
?>

方法 #3：更多选项

使用 PHP 的 php_tidy 修复损坏的 HTML，或完全去除 HTML 的选项。

function summarise( $input, $break = " ", $end_text = "...", $limit = 255, $tidy_html = 1, $strip_html = 0 ) {
               if ( strlen( $input ) >= $limit ) {
                       $breakpoint = strpos( $input, $break, $limit );
                       $input = substr( $input, 0, $breakpoint ) . $end_text;
               }
               if ( $tidy_html == 1 ) {
                       ob_start(  );
                       $tidy = new tidy;
                       $config = array( 'indent' => true, 'output-xhtml' => true, 'wrap' => 200, 'clean' => true, 'show-body-only' => true );
                       $tidy->parseString( $input, $config, 'utf8' );
                       $tidy->cleanRepair(  );
                       $input = $tidy;
               }
               if ( $strip_html == 1 ) {
                       $input = strip_tags( $input );
               }
               return $input;
}

方法 #4：无需函数

<?php

$long_text = "Lorem ipsum dolor sit amet, consectetur adipiscing elit.";
$max_length = 40; // we want to show only 40 characters.

if (strlen($long_text) > $max_length)
{
 $short_text = (substr($long_text,0,$max_length-1)); // make it $max_length chars long
 $short_text .= "..."; // add an ellipses ... at the end
 $short_text .= "<a href='http://example.com/page.html'>Read more</a>"; // add a link
 echo $short_text;
}
else
{
// string is already less than $max_length, so display the string as is
echo $long_text;
}

?>