探讨PHP实现站内搜索引擎的具体方法_PHP教程

<OL class=dp-xml><LI class=alt><SPAN><SPAN class=tag><STRONG><FONT color=#006699><?</FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><SPAN class=tag-name><STRONG><FONT color=#006699>include</FONT></STRONG></SPAN><SPAN>("include/common.inc");   </SPAN></SPAN><LI class=alt><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>title</FONT></SPAN><SPAN> = </SPAN><SPAN class=attribute-value><FONT color=#0000ff>"Search"</FONT></SPAN><SPAN>;   </SPAN></SPAN><LI class=""><SPAN>include("include/header.inc");   </SPAN><LI class=alt><SPAN></SPAN><SPAN class=tag><STRONG><FONT color=#006699>?></FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>P</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>   </SPAN></SPAN><LI class=alt><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>FORM</SPAN></FONT></STRONG><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>ACTION</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"<? echo "</FONT></SPAN><SPAN>$PHP_SELF"; </SPAN><SPAN class=tag><STRONG><FONT color=#006699>?></FONT></STRONG></SPAN><SPAN>" </SPAN><SPAN class=attribute><FONT color=#ff0000>METHOD</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"POST"</FONT></SPAN><SPAN class=tag><STRONG><FONT color=#006699>></FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>INPUT</SPAN></FONT></STRONG><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>TYPE</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"text"</FONT></SPAN><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>NAME</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"searchstr"</FONT></SPAN><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>value</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"<? echo "</FONT></SPAN><SPAN>$searchstr"; </SPAN><SPAN class=tag><STRONG><FONT color=#006699>?></FONT></STRONG></SPAN><SPAN>"   </SPAN></SPAN><LI class=alt><SPAN></SPAN><SPAN class=attribute><FONT color=#ff0000>SIZE</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"20"</FONT></SPAN><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>MAXLENGTH</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"30"</FONT></SPAN><SPAN class=tag><STRONG><FONT color=#006699>></FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>INPUT</SPAN></FONT></STRONG><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>TYPE</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"submit"</FONT></SPAN><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>VALUE</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>"Search!"</FONT></SPAN><SPAN class=tag><STRONG><FONT color=#006699>></FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=alt><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag></</SPAN><SPAN class=tag-name>FORM</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag></</SPAN><SPAN class=tag-name>P</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>   </SPAN></SPAN><LI class=alt><SPAN></SPAN><SPAN class=tag><STRONG><FONT color=#006699><?</FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><SPAN class=tag-name><STRONG><FONT color=#006699>if</FONT></STRONG></SPAN><SPAN> ( ! empty($searchstr) )   </SPAN></SPAN><LI class=alt><SPAN>{   </SPAN><LI class=""><SPAN>// empty()用来检查查询字串是否为空   </SPAN><LI class=alt><SPAN>// 如果不为空，调用grep查询   </SPAN><LI class=""><SPAN>echo "</SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>HR</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>n";   </SPAN></SPAN><LI class=alt><SPAN>// 调用grep对所有文件进行大小写非敏感模式的查询   </SPAN><LI class=""><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>cmdstr</FONT></SPAN><SPAN> = </SPAN><SPAN class=attribute-value><FONT color=#0000ff>"grep -i $searchstr *"</FONT></SPAN><SPAN>;   </SPAN></SPAN><LI class=alt><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>fp</FONT></SPAN><SPAN> = </SPAN><SPAN class=attribute-value><FONT color=#0000ff>popen</FONT></SPAN><SPAN>( $cmdstr, "r" ); // 执行命令并输出管道   </SPAN></SPAN><LI class=""><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>myresult</FONT></SPAN><SPAN> = </SPAN><SPAN class=attribute-value><FONT color=#0000ff>array</FONT></SPAN><SPAN>(); // 存储查询结果   </SPAN></SPAN><LI class=alt><SPAN>while( $</SPAN><SPAN class=attribute><FONT color=#ff0000>buffer</FONT></SPAN><SPAN> = </SPAN><SPAN class=attribute-value><FONT color=#0000ff>fgetss</FONT></SPAN><SPAN> ($fp, 4096))   </SPAN></SPAN><LI class=""><SPAN>{   </SPAN><LI class=alt><SPAN>// grep返回这样格式： 文件名：匹配字串出现行数   </SPAN><LI class=""><SPAN>// 因此我们利用函数split()分离处理数据   </SPAN><LI class=alt><SPAN>list($fname, $fline) = split(":",$buffer, 2);   </SPAN><LI class=""><SPAN>// 我们只输出第一次匹配的结果   </SPAN><LI class=alt><SPAN>if ( !defined($myresult[$fname]))   </SPAN><LI class=""><SPAN>$myresult[$fname] = $fline;   </SPAN><LI class=alt><SPAN>}   </SPAN><LI class=""><SPAN>// 现在我们将结果存储在数组中，下面就可以处理并输出了   </SPAN><LI class=alt><SPAN>if ( count($myresult) )   </SPAN><LI class=""><SPAN>{   </SPAN><LI class=alt><SPAN>echo "</SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>OL</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>n";   </SPAN></SPAN><LI class=""><SPAN>while(list($fname,$fline) = each($myresult))   </SPAN><LI class=alt><SPAN>echo "</SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>LI</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>A</SPAN></FONT></STRONG><SPAN> </SPAN><SPAN class=attribute><FONT color=#ff0000>HREF</FONT></SPAN><SPAN>="$fname"</SPAN><SPAN class=tag><STRONG><FONT color=#006699>></FONT></STRONG></SPAN><SPAN>$fname</SPAN><STRONG><FONT color=#006699><SPAN class=tag></</SPAN><SPAN class=tag-name>A</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN> : $fline </SPAN><STRONG><FONT color=#006699><SPAN class=tag></</SPAN><SPAN class=tag-name>LI</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>n";   </SPAN></SPAN><LI class=alt><SPAN>echo "</SPAN><STRONG><FONT color=#006699><SPAN class=tag></</SPAN><SPAN class=tag-name>OL</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>n";   </SPAN></SPAN><LI class=""><SPAN>}   </SPAN><LI class=alt><SPAN>else   </SPAN><LI class=""><SPAN>{   </SPAN><LI class=alt><SPAN>// 如果没有查询结果   </SPAN><LI class=""><SPAN>echo "Sorry. Search on </SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>B</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>$searchstr</SPAN><STRONG><FONT color=#006699><SPAN class=tag></</SPAN><SPAN class=tag-name>B</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>   </SPAN></SPAN><LI class=alt><SPAN>returned no results.</SPAN><STRONG><FONT color=#006699><SPAN class=tag><</SPAN><SPAN class=tag-name>BR</SPAN><SPAN class=tag>></SPAN></FONT></STRONG><SPAN>n";   </SPAN></SPAN><LI class=""><SPAN>}   </SPAN><LI class=alt><SPAN>pclose($fp);   </SPAN><LI class=""><SPAN>}   </SPAN><LI class=alt><SPAN></SPAN><SPAN class=tag><STRONG><FONT color=#006699>?></FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=""><SPAN></SPAN><SPAN class=tag><STRONG><FONT color=#006699><?</FONT></STRONG></SPAN><SPAN>   </SPAN></SPAN><LI class=alt><SPAN></SPAN><SPAN class=tag-name><STRONG><FONT color=#006699>include</FONT></STRONG></SPAN><SPAN>("include/footer.inc");   </SPAN></SPAN><LI class=""><SPAN></SPAN><SPAN class=tag><STRONG><FONT color=#006699>?></FONT></STRONG></SPAN><SPAN>  </SPAN></SPAN></LI></OL>