如何实现“点击查看更多”功能?

时间:2010-06-07 14:18:47

标签: string internationalization

我们经常会看到显示文章前几行的网站,然后附加... [更多],以便有兴趣的人可以点击它来查看完整的文章。

要实现此功能,我们首先需要找出应该剪切文章文本的位置以附加... [更多]。

由于必须有一些HTML / CSS与文章文本相结合,我们必须记住在计算文本长度时忽略它们。

但有些东西我无法弄明白,如果在文章文本的前几行中混合使用多种语言,则文本的长度将非常难以计算,因为字符可以是可变长度。

我们应该如何解决这个问题?

1 个答案:

答案 0 :(得分:1)

我不确切知道这个来源的确切来源,但我一直在使用这段代码,你会在其评论中找到解释:

/**
* @desc Cut given plain/HTML text nicely
* @param string text to cut
* @param int approximetly length of desired text length
* @param int optional length, how far text can variante from approximetly length
* @param bool optional can we cut words
* @param bool optional do we need to append three dots to the end of cutted text
* @return string cutted text
*/

function htmlSubstr($text, $approxLength, $lengthOffset = 20, $cutWords = FALSE, $dotsAtEnd = TRUE) {
    mb_internal_encoding('UTF-8');
    // $approxLength:
    // The approximate length you want the concatenated text to be

    // $lengthOffset:
    // The variation in how long the text can be in this example text
    // length will be between 200 and 200-20=180 characters and the
    // character where the last tag ends
    // Reset tag counter & quote checker
    $tag_counter = 0;
    $quotes_on = FALSE;

    // Check if the text is too long
    if (mb_strlen($text) > $approxLength) {
        // Reset the tag_counter and pass through (part of) the entire text
        $c = 0;
        for ($i = 0; $i < mb_strlen($text); $i++) {
            // Load the current character and the next one
            // if the string has not arrived at the last character
            $current_char = mb_substr($text,$i,1);
            if ($i < mb_strlen($text) - 1) {
                $next_char = mb_substr($text,$i + 1,1);
            } else {
                $next_char = "";
            }

            // First check if quotes are on
            if (!$quotes_on) {
                // Check if it's a tag
                // On a "<" add 3 if it's an opening tag (like <a href...)
                // or add only 1 if it's an ending tag (like </a>)
                if ($current_char == '<') {
                    if ($next_char == '/') {
                        $tag_counter += 1;
                    } else {
                        $tag_counter += 3;
                    }
                }

                // Slash signifies an ending (like </a> or ... />)
                // substract 2
                if ($current_char == '/' && $tag_counter <> 0) $tag_counter -= 2;
                // On a ">" substract 1
                if ($current_char == '>') $tag_counter -= 1;
                // If quotes are encountered, start ignoring the tags
                // (for directory slashes)
                if ($current_char == '"') $quotes_on = TRUE;
            } else {
                // IF quotes are encountered again, turn it back off
                if ($current_char == '"') $quotes_on = FALSE;
            }

            // Count only the chars outside html tags
            if($tag_counter == 2 || $tag_counter == 0) $c++;

            // Check if the counter has reached the minimum length yet,
            // then wait for the tag_counter to become 0, and chop the string there
            if ($c > $approxLength - $lengthOffset && $tag_counter == 0 && ($next_char == ' ' || $cutWords == TRUE)) {
                $text = mb_substr($text,0,$i + 1);
                if($dotsAtEnd){
                    $text .= '...';
                }

                return $text;
            }
        }
    }
    return $text;
}