M2 討論區

Title: php去除html标识截取字符串 [Print]
Author: admin    Time: 2011-11-22 12:11
Title: php去除html标识截取字符串
最近需要在HTML的内容中提取一段文本作为简介，如果用普通的办法提取那么将有可能出现截取了半个HTML标志的情况，会破坏页面布局， 为此添加了这么一个函数，可完美解决此问题！！注意在这里你截取的字符数是不含HTML标志的！！
  1. <?php   
    0 v( H0 i% E" b6 F, B/ ~9 R, S
  2. /**  
    3 s* b1 l- x0 ?! k- f. h6 G
  3. * 截取HTML字符串 允许忽略HTML标志不计  
    1 Y" b0 r0 g1 T
  4. *  6 w, P+ Z! {" s. ?" ]! C
  5. * Author：学无止境  
    6 M0 M9 o( B3 K
  6. * Email：xjtdy888@163.com  
    9 G8 E' Q8 j1 _5 t7 r4 m5 \+ s
  7. * QQ: 339534039  
    9 I+ j: E. P' i8 p( V
  8. * Home:http://www.phpos.org  8 H/ ?, ], v- d
  9. * Blog:http://hi.baidu.com/phps  
    % Q( h3 q  R) |7 ^, _8 l
  10. *  % D7 f1 W1 w8 P
  11. * 转载请保留作者信息  
    7 O1 _4 ^0 d2 L. k
  12. & m5 Y4 f2 c3 e- C' y
  13. *   
    # l: f. M# O6 w; o0 }3 U* W
  14. * @param 要截取的HTML $str  5 b5 P9 g  O5 G3 v9 L
  15. * @param 截取的数量 $num  
    * O5 g# y# J" `
  16. * @param 是否需要加上更多 $more  + }/ b0 C# A' U* s, Y9 a- N8 R
  17. * @return 截取串  6 ~5 `" m5 t  ?' [$ F+ m
  18. */  & ]/ n" T4 c5 O# P% F- B; a! f
  19. function phpos_chsubstr_ahtml($str,$num,$more=false)   
    , ]# C  C* Q7 ?$ i8 |8 y& f# J
  20. {   
    9 E: G0 O) X% J2 r
  21.     $leng=strlen($str);   
    + X, \4 p. G  w: A
  22.       if($num>=$leng)      return $str;   
    & x& ~- o/ Y5 |2 S& }0 p$ P
  23.     $word=0;   . o* M  v$ p* }% H1 J* d! N; _' n' Y
  24.     $i=0;                        /** 字符串指针 **/  5 y% N& x$ c+ Z; A7 Q1 j
  25.     $stag=array(array());        /** 存放开始HTML的标志 **/  
    , e1 d& I  a2 \# [
  26.     $etag=array(array());        /** 存放结束HTML的标志 **/  + V. F  i- `4 u6 x. H% r# d
  27.     $sp = 0;   
    & w6 C4 J8 H' G; G" d6 r9 F
  28.     $ep = 0;   
    4 j1 ~1 Q8 {& ^- |8 E
  29.       while($word!=$num)   
    % K0 |3 o% d5 W5 x
  30.       {   
    5 H9 L4 l. n6 p, u5 P1 ^% `0 D
  31.   
      z2 A( W# O/ z* B, w
  32.           if(ord($str[$i])>128)   1 W$ r: h( X* L( w& ^! O
  33.           {   9 ~9 P' f: L: ~% w/ x9 g
  34.             //$re.=substr($str,$i,3);   
    ' \/ E/ O! ^2 N
  35.             $i+=3;   
    * F$ Y7 d4 c6 ^, ]$ M8 _
  36.             $word++;   ( A' S# O1 @# Q7 S2 `2 ]
  37.           }   
    4 C, `% Z3 O0 @9 B; u
  38.           else if ($str[$i]=='<')   
      U  n) Q* F1 E* ]% j
  39.           {   
    7 V! A2 A1 S0 h
  40.               if ($str[$i+1] == '!')   # g& ^) t3 k% |+ i6 q0 E  I% `5 O* g6 {
  41.               {   + k+ D' X% j5 t% g+ B" ~$ B, y
  42.                 $i++;   % Q( c+ c2 h. M) `& M5 k
  43.                   continue;   
    ) N* e# M9 n1 l$ v  |0 J- @; s2 P
  44.               }   
    & Q1 L1 I2 i2 R8 p0 |/ V
  45.   
    $ l. d. n) s) N! y) M; \( V0 K: V" h3 ^
  46.               if ($str[$i+1]=='/')       3 y2 }' T  Y$ Z( J! n' E7 J0 g
  47.               {   
    % T, g* R# N9 S1 r- W, E( q' Y
  48.                 $ptag=$etag ;   ' M* q2 ]$ A1 M
  49.                 $k=$ep;   
    5 }3 g/ c- Z! I8 \6 H& a; ~# T
  50.                 $i+=2;   
    * N6 v7 S( O3 e3 r) Y. l2 K
  51.               }   
    + ?2 f' J: y7 ?
  52.               else                       
    3 S1 c+ D8 u1 c* {
  53.               {   2 d2 }$ z2 z- ^! t* ^3 ]/ h' r# b
  54.                 $ptag=$stag;   
    ; f$ l. v1 }2 Z7 f# y6 B5 P; ]# I/ t
  55.                 $i+=1;   1 t- p6 P; _# K, _
  56.                 $k=$sp;   * B4 \% [, L" G7 I  K4 O
  57.               }   1 @$ U9 B& r" ~) W
  58.   
    ; k9 {4 x# p+ d* a( a. \/ J
  59.               for(;$i<$leng;$i++)           2 _8 U: \) F" F7 C4 y
  60.               {   $ U, f' |. U0 S+ H7 ^4 j. y
  61.                   if ($str[$i] == ' ')   ) z" |# }# U% H9 V
  62.                   {   ' }! G$ V- S1 k6 @4 ?
  63.                     $ptag[$k] = implode('',$ptag[$k]);   . o5 u5 J! t' U" r: r
  64.                     $k++;   # D' R5 D5 v' ?. U3 o
  65.                       break;   & Y" [  c" C6 B. r
  66.                   }   ( ]0 T, u6 D/ L
  67.                   if ($str[$i] != '>')   
    $ V' t7 Q2 y- S4 ]4 @) S$ E
  68.                   {   
    ) A* u- J$ u4 @0 m
  69.                     $ptag[$k][]=$str[$i];   1 t; H! z$ T2 P6 s8 B
  70.                       continue;   ! k0 G  ]9 E2 A( u/ ?: w' t
  71.                   }   4 |- h8 {8 M8 i4 R7 E& y
  72.                   else                  
    3 N, F: k: K+ p
  73.                   {   3 v+ f, z7 A1 }! ~( I
  74.                     $ptag[$k] = implode('',$ptag[$k]);   1 ^/ d0 E( `& [; w5 S4 Q
  75.                     $k++;   2 B) u2 g2 J1 e/ n! t$ t1 L
  76.                       break;   + u* u% b2 @, p: R+ o7 S1 O# n' }( X3 A
  77.                   }   
    . I' j& ?0 H9 k6 B( o
  78.               }   * @; f8 J( `. x8 }) v2 F+ _) ~
  79.             $i++;   ' q( F& R5 r- M4 l5 m
  80.               continue;   
    % L8 f1 o8 c$ C$ Y  L$ I
  81.           }     t# q& j& ]. G+ e4 j4 A
  82.           else  
    + ^* I5 p' g5 |% u9 Q; Q1 F
  83.           {   
    ; h. ^, R& p& l2 t& B
  84.             //$re.=substr($str,$i,1);   
    5 u5 c$ S9 s; m# D3 H$ }
  85.             $word++;   - Y" d5 h- _6 V
  86.             $i++;   
    1 i$ j0 A1 a' s, G9 R
  87.           }     T  v/ d1 C* B
  88.       }   5 E! v: T- W" g4 a
  89.       foreach ($etag as $val)   
    $ K  z( o" T" V$ w, F& W: ?; e
  90.       {   8 h3 \- L  b0 }7 J( e( ?/ {
  91.         $key1=array_search($val,$stag);   
    4 q# [9 T+ {: F, v7 |+ t
  92.           if ($key1 !== false)          unset($stag[$key]);   
    : x& d' ]$ U5 x) K2 c9 T
  93.       }   
    ! b8 F' K$ c- z
  94.       foreach ($stag as $key => $val)   
    4 r' ^0 k7 ~. W0 D& }( C
  95.       {   
    . ]& X' t0 V: o0 |  i2 ~
  96.           if (in_array($val,array('br','img'))) unset($stag[$key1]);   
    6 J% n2 N, m6 A. J  _3 x$ j
  97.       }   ' i+ p/ h+ J. _
  98.     array_reverse($stag);   ; C3 V! Z8 v* Z  n- @, A6 B. Y" T
  99.     $ends = '</'.implode('></',$stag).'>';   
    5 G' D, A9 L. e' L& v3 l# V
  100.     $re = substr($str,0,$i).$ends;   
    ) I7 f  g5 m4 U! x# Z! E" ^, K
  101.       if($more)    $re.='...';   & {- B0 }: S$ b0 D9 [* I! _6 a
  102.       return $re;   
      F; W0 }0 d; m0 J. f2 i8 C9 u2 Q; w
  103. }   ( K' D+ a1 M+ {! K
  104.   
    & B7 ?3 D0 D! H7 G7 N
  105. $str=<<<EOF   ' \8 X* D3 S( y4 t& R$ o
  106. <h3>What is the <acronym>GNU</acronym> pr<a><a><a>oject?</h3>   
    6 I; i, ~1 c1 t8 z) H  @9 N  u
  107. <p>The <acronym>GNU</acronym> Project was launched in 1984 to develop a complete Unix-like operating system which is <a href="http://www.gnu.org/philosophy/free-sw.html">free software</a>: the <acronym>GNU</acronym> system. Variants of the <acronym>GNU</acronym> operating system, which use the kernel called Linux, are now widely used; though these systems are often referred to as “Linux”, they are more accurately called <a href="http://www.gnu.org/gnu/linux-and-gnu.html">GNU/Linux systems</a>. </p>   
    ( F  n! z6 }$ J$ Z  M* M  \1 w+ r
  108. <p><acronym>GNU</acronym> is a recursive acronym for “GNU's Not Unix”; it is pronounced <em>guh-noo</em>, approximately like <em>canoe</em>.</p>  0 b2 G" m& j! J4 j* w) u  E( v
  109. <h3>What is Free Software?</h3>  - d0 v# @' K! c) t+ p8 m  m# [
  110. <p>“<a href="http://www.gnu.org/philosophy/free-sw.html">Free software</a>” is a matter of liberty, not price. To understand the concept, you should think of “free” as in “free speech”, not as in “free beer”.</p>  + M' }# s- m' F' m' P% W
  111. <p>Free software is a matter of the users' freedom to run, copy, distribute, study, change and improve the software. More precisely, it refers to four kinds of freedom, for the users of the software:</p>   % j/ P' B# Q9 w7 ^  P  p5 D* `+ M8 m
  112. <ul>   7 y" P: T7 u$ y
  113.       <li>The freedom to run the program, for any purpose (freedom 0). </li>   
    9 n+ |8 s6 L, u7 m
  114.       <li>The freedom to study how the program works, and adapt it to your needs (freedom 1). Access to the source code is a precondition for this. </li>   * z' @+ x4 y* ^! J) n
  115.       <li>The freedom to redistribute copies so you can help your neighbor (freedom 2). </li>   
    , k1 {  Z+ T, w9 Q( C
  116.       <li>The freedom to improve the program, and release your improvements to the public, so that the whole community benefits (freedom 3). Access to the source code is a precondition for this. </li>   
    % k, E" p( M1 Y( w0 s- _' ^
  117. </ul>   
    ; y( w) b5 @8 G, R6 e( t: N
  118. <h3>What is the Free Software Foundation?</h3>   
    4 }6 t3 S6 u/ Y7 S
  119. <p>The <a href="http://www.fsf.org/">Free Software Foundation</a> (<abbr title="Free Software Foundation">) is the principal organizational sponsor of the Project. The receives very little funding from corporations or grant-making foundations, but relies on support from individuals like you. </abbr>) is the principal organizational sponsor of the Project. The receives very little funding from corporations or grant-making foundations, but relies on support from individuals like you. </p>   8 ?$ k# J0 Z$ l, u4 G5 @
  120. <p>Please consider helping the <abbr>by , or by . If you use Free Software in your business, you can also consider or as a way to support the . </abbr>by , or by . If you use Free Software in your business, you can also consider or as a way to support the . </p>   
    ) W% q* m. S5 p- y$ g
  121. <p>The <acronym>GNU</acronym> project supports the mission of the <abbr>to preserve, protect and promote the freedom to use, study, copy, modify, and redistribute computer software, and to defend the rights of Free Software users. We support the on the Internet, , and the unimpeded by private monopolies. You can also learn more about these issues in the book . </abbr>to preserve, protect and promote the freedom to use, study, copy, modify, and redistribute computer software, and to defend the rights of Free Software users. We support the on the Internet, , and the unimpeded by private monopolies. You can also learn more about these issues in the book . </p>   8 I3 F6 {  y( l" j
  122. <!--   6 l) d- P" G5 P
  123. Keep link lines at 72 characters or lynx will break them poorly   - K) v' w7 Z& A4 O: V
  124. Obviously, we list ONLY the most useful/important URLs here   
      ?" {* G# R+ \9 h) e, a
  125. Keep it short and sweet: 3 lines and 2 columns is already enough   
    . b( w; t: ]) e( B2 f% u
  126. --><!-- BEGIN GNUmenu -->   2 f4 S/ h. g7 F; h/ I  j5 h. c
  127. EOF;   
    : [* Q$ s+ c& S  e
  128. echo phpos_chsubstr_ahtml($str,800);   
    4 m0 P$ Y4 K/ L" P" @
  129. ?>   - K: o" y+ q9 e8 ^( @4 |
Copy




Welcome M2 討論區 (https://forum.m2.hk/) Powered by Discuz! X2.5