如果您的网站是静态页面（用静态页面的好处不多说了），而你的虚拟主机以支持PHP，那么用PHP 做站内的搜索引擎是个不错的选择！
源代码如下:
<?PHP
/****************************************************
文件名：search.php
源作者:不详
修改者：sunthing.xie/sanxin.xie
调用方法：
<form method="post" action="search.php">
<input type="text" name="key" size=40 value="">
<input type="submit" value="search">
</form>
sunthing 的主页：http://gems.51.net
三新期盼欢迎和大家一起交流
****************************************************/
if (function_exists("set_time_limit") && !get_cfg_var('safe_mode')){
set_time_limit(600);
}
$doc_path= $_SERVER["DOCUMENT_ROOT"];
$doc_path_len=strlen($doc_path);
if(substr($doc_path,-1)!="/"){
$doc_path=$doc_path."/";
}
function get_msg($path){
global $key, $i;
$handle = opendir($path);
while ($filename = readdir($handle)) {
$newpath = $path."/".$filename;
if (is_file($newpath)) {
if (substr($newpath,0,3)!='./.'){
$fp = fopen($newpath, "r");
$msg = fread($fp, filesize($newpath));
fclose($fp);
match_show($key, $msg, $newpath, $filename);
}
}
if (is_dir($path."/".$filename) && ($filename != ".") && ($filename != "..")) {
get_msg($path."/".$filename);
}
}
closedir($handle);
return $i;
}
function match_show($key, $msg, $newpath, $filename) {
global $ar, $i,$doc_path;
$key = chop($key);
if($key){
$msg = preg_replace("/<style>.+<\/style>/is", "", $msg);
$msg = str_replace(" ", " ", $msg);
$msg = preg_replace("/<[^>]+>/", "", $msg);
$value = preg_match("/.*$key.*/i", $msg, $res);
if($value) {
$res[0] = preg_replace("/$key/i", "<FONT COLOR=\"red\">$key</FONT>", $res[0]);
$i++;
$link =str_replace($doc_path,"",$newpath);
$ar[] = "<font size=\"3\">$i.</font><a href=\"/$link\"><FONT face=\"verdana\" size=\"2\">$filename</FONT></a><BR><BR><FONT face=\"verdana\" size=\"2\">".$res[0]."</FONT><BR><br>";
}
}else {
echo "Please Enter Keywords";
exit;
}
}
/****************开始搜索部分************************/
//$i = get_msg("detailedpage");//指定从什么目录搜索
$i=get_msg($doc_path."demo");
if (empty($page)) $page=1;
$maxresult=($page*10);
$resultcount = count($ar);
if ($resultcount==0){
echo" <font color=\"red\"><h2>Sorry, no matches were found. </font></h2> <br>Please try again using different search words. <br><br>";
}else{
if($resultcount%10==0){
$maxpageno=$resultcount/10;
}else{
$maxpageno=floor($resultcount/10)+1;
}
if ($page>$maxpageno){
$page=$maxpageno;
$pagemax=$resultcount-1;
$pagemin=max(0,$result_count-10);
}elseif($page==1){
$pagemin=0; $pagemax=min($result_count-1,10-1);
}else{
$pagemin=min($resultcount-1,10*($page-1));
$pagemax=min($resultcount-1,$pagemin+10-1);
}
$maxresult=min($maxresult,$resultcount);
echo "<p align=\"center\">";
echo "<br><h1 align=center>Search Results</h1>";
echo "</p><hr noshade size='1' color='#336699'>";
for ($i=max(0,$maxresult-10); $i<$maxresult; $i++) {
print $ar[$i];
}
echo "<hr size='1' noshade><p align=\"center\">";
echo " <font face=\"verdana\" size=\"2\">Search $resultcount info </font>";
$nextpage=$page+1;
$previouspage=$page-1;
echo " --- [ <a href='search.php?key=$key&page=".($page-1)."' target='_self'> <font face=\"verdana\" size=\"2\">Forward 10 <font face=\"verdana\"></a> ]";
echo "[ <a href='search.php?key=$key&page=".($page+1)."' target='_self'> <font face=\"verdana\" size=\"2\">Next 10 <font face=\"verdana\"></a> ] </p>";
}
?>