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PHP intercepts HTML string and automatically completes HTML tag_PHP tutorial

WBOYOriginal: 2016-07-20 11:11:08977browse

文章来总结一下关于利用php截取html字符串自动补全html标签，实际开发中会经常碰到，很多人直接先strip_tags过滤掉html标签，但是就只剩下纯文本了，可读性非常差，下面是一个函数

代码如下

复制代码

/**
* 截取HTML,并自动补全闭合
* @param $html
* @param $length
* @param $end
*/
function subHtml($html,$length) {
$result = '';
$tagStack = array();
$len = 0;

$contents = preg_split("~(<[^>]+?>)~si",$html, -1,PREG_SPLIT_NO_EMPTY| PREG_SPLIT_DELIM_CAPTURE);
foreach($contents as $tag)
{
if (trim($tag)=="") continue;
if(preg_match("~<([a-z0-9]+)[^/>]*?/>~si",$tag)){
$result .= $tag;
}else if(preg_match("~]*?>~si",$tag,$match)){
if($tagStack[count($tagStack)-1] == $match[1]){
array_pop($tagStack);
$result .= $tag;
}
}else if(preg_match("~<([a-z0-9]+)[^/>]*?>~si",$tag,$match)){
array_push($tagStack,$match[1]);
$result .= $tag;
}else if(preg_match("~~si",$tag)){
$result .= $tag;
}else{
if($len + mstrlen($tag) < $length){
$result .= $tag;
$len += mstrlen($tag);
}else {
$str = msubstr($tag,0,$length-$len+1);
$result .= $str;
break;
}

}
}
while(!empty($tagStack)){
$result .= '';
}
return $result;
}

/**
* 截取中文字符串
* @param $string 字符串
* @param $start 起始位
* @param $length 长度
* @param $charset 编码
* @param $dot 附加字串
*/
function msubstr($string, $start, $length,$dot='',$charset = 'UTF-8') {
$string = str_replace(array('&', '"', '<', '>',' '), array('&', '"', '<', '>',' '), $string);
if(strlen($string) <= $length) {
return $string;
}

if(strtolower($charset) == 'utf-8') {
$n = $tn = $noc = 0;
while($n < strlen($string)) {
$t = ord($string[$n]);
if($t == 9 || $t == 10 || (32 <= $t && $t <= 126)) {
$tn = 1; $n++;
} elseif(194 <= $t && $t <= 223) {
$tn = 2; $n += 2;
} elseif(224 <= $t && $t <= 239) {
$tn = 3; $n += 3;
} elseif(240 <= $t && $t <= 247) {
$tn = 4; $n += 4;
} elseif(248 <= $t && $t <= 251) {
$tn = 5; $n += 5;
} elseif($t == 252 || $t == 253) {
$tn = 6; $n += 6;
} else {
$n++;
}
$noc++;
if($noc >= $length) {
break;
}
}
if($noc > $length) {
$n -= $tn;
}
$strcut = substr($string, 0, $n);
} else {
for($i = 0; $i < $length; $i++) {
$strcut .= ord($string[$i]) > 127 ? $string[$i].$string[++$i] : $string[$i];
}
}

return $strcut.$dot;
}

/**
* 取得字符串的长度，包括中英文。
*/
function mstrlen($str,$charset = 'UTF-8'){
if (function_exists('mb_substr')) {
$length=mb_strlen($str,$charset);
} elseif (function_exists('iconv_substr')) {
$length=iconv_strlen($str,$charset);
} else {
preg_match_all("/[x01-x7f]|[xc2-xdf][x80-xbf]|xe0[xa0-xbf][x80-xbf]|[xe1-xef][x80-xbf][x80-xbf]|xf0[x90-xbf][x80-xbf][x80-xbf]|[xf1-xf7][x80-xbf][x80-xbf][x80-xbf]/", $text, $ar);
$length=count($ar[0]);
}
return $length;
}

Example

The code is as follows

Copy code

* @param HTML to be intercepted $str
* @param The intercepted quantity $num
* @param Whether to add more $more
* @return The intercepted string
*/
function phpos_chsubstr_ahtml($str,$num, $more=false)
{
$leng=strlen($str);
if($num>=$leng) return $str;
$word=0;
$i =0; >*/
$sp = 0;
$ep = 0;
while($word!=$num)
{

if(ord($str[$i ])>128)

🎜 > else if ($str[$i]=='<')

$ptag=&$etag ;
$k =&$ep;
$ptag=&$stag;
$i+=1;
$k=& $sp;
}

              for(;$i<$leng;$i++)
              {
                  if ($str[$i] == ' ')
                  {
                    $ptag[$k] = implode('',$ptag[$k]);
                    $k++;
                      break;
                  }
                  if ($str[$i] != '>')
                  {
                    $ptag[$k][]=$str[$i];
                      continue;
                  }
                  else
                  {
                    $ptag[$k] = implode('',$ptag[$k]);
                    $k++;
                      break;
                  }
              }
            $i++;
              continue;
          }
          else
          {
            //$re.=substr($str,$i,1);
            $word++;
            $i++;
          }
      }
      foreach ($etag as $val)
      {
        $key1=array_search($val,$stag);
          if ($key1 !== false)          unset($stag[$key]);
      }
      foreach ($stag as $key => $val)
      {
          if (in_array($val,array('br','img'))) unset($stag[$key1]);
      }
    array_reverse($stag);
    $ends = '';
    $re = substr($str,0,$i).$ends;
      if($more)    $re.='...';
      return $re;
}

PHP intercepts strings and generates article abstracts
When we write BLOG, we often need to display the previous part of the article, but we are afraid that improper truncation will destroy the closing tag and cause damage to the entire document structure

The code is as follows

代码如下

复制代码

function text_zhaiyao($text,$length){ //文章摘要生成函数 $test:内容 $length:摘要长度
    global $Briefing_Length;
    mb_regex_encoding("UTF-8");
    if(mb_strlen($text) <= $length ) return $text;
$Foremost = mb_substr($text, 0, $length);
$re = "<(/?)
(P|DIV|H1|H2|H3|H4|H5|H6|ADDRESS|PRE|TABLE|TR|TD|TH|INPUT|SELECT|TEXTAREA|OBJECT|A|UL|OL|LI|
BASE|META|LINK|HR|BR|PARAM|IMG|AREA|INPUT|SPAN)[^>]*(>?)";
    $Single = "/BASE|META|LINK|HR|BR|PARAM|IMG|AREA|INPUT|BR/i";

    $Stack = array(); $posStack = array();

    mb_ereg_search_init($Foremost, $re, 'i');

    while($pos = mb_ereg_search_pos()){
    $match = mb_ereg_search_getregs();
    /* [Child-matching Formulation]:

    $matche[1] : A "/" charactor indicating whether current "<...>" Friction is
    Closing Part
    $matche[2] : Element Name.
    $matche[3] : Right > of a "<...>" Friction
    */
    if($match[1]==""){
    $Elem = $match[2];
    if(mb_eregi($Single, $Elem) && $match[3] !=""){
    continue;
    }

Copy code

function text_zhaiyao($text,$length){ //Article summary generation function $test:content$length:summary length

global $Briefing_Length;
mb_regex_encoding("UTF-8"); if( mb_strlen($text) <= $length ) return $text;

$Foremost = mb_substr($text, 0, $length);

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