This article introduces every steps of the development, including both design and PHP programming. Basic computer skills and knowledge of HTML fundamentals are required. Ok, let's begin now.
Step 1: Design Search Box Under your website root, make a file called search.htm or anything you like and type in the following code:
<html>
<head>
<title>Web Search</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<form name="form1" method="post" action="search.php">
<table width="100%" cellspacing="0" cellpadding="0">
<tr>
<td width="36%">
<div align="center">
<input type="text" name="keyword">
</div>
</td>
<td width="64%">
<input type="submit" name="Submit" value="Search">
</td>
</tr>
</table>
</form>
</body>
</html>
Step 2: Write search.php file. It is the core of your website search engine.
Under your website root, create a file called search.php or anything you like. <?php
//get keywords
$keyword=trim($_POST["keyword"]);
//check if the keyword is empty
if($keyword==""){
echo"no keywords";
exit;
}
?>
With above, you can give hints to your users when they forget to enter a keyword. Now let's go through all the files or articles in your website.
<?php
function listFiles($dir){
$handle=opendir($dir);
while(false!==($file=readdir($handle))){
if($file!="."&&$file!=".."){
//if it is a directory, then continue
if(is_dir("$dir/$file")){
listFiles("$dir/$file");
}
else{
//process the searching here with the following PHP script
}
}
}
}
?>
The following scripts read, process files and check whether the files contain $keyword. If $keyword is found in the file, the file address will be saved in an array-type variable.
<?php
function listFiles($dir,$keyword,&$array){
$handle=opendir($dir);
while(false!==($file=readdir($handle))){
if($file!="."&&$file!=".."){
if(is_dir("$dir/$file")){
listFiles("$dir/$file",$keyword,$array);
}
else{
//read file
$data=fread(fopen("$dir/$file","r"),filesize("$dir/$file"));
//avoid search search.php itself
if($file!="search.php"){
//contain keyword?
if(eregi("$keyword",$data)){
$array[]="$dir/$file";
}
}
}
}
}
}
//define array $array
$array=array();
//execute function
listFiles(".","php",$array);
//echo/print search results
foreach($array as $value){
echo "$value"."
\n";
} ?>
Now, combine the programs listed above, you will find all the related results in your websites will be found and listed. A further optimization of the search engine can be taken by adding the following,
1,list the title of all searching results
REPLACE THE FOLLOWING
if(eregi("$keyword",$data)){
$array[]="$dir/$file";
}
WITH
if(eregi("$keyword",$data)){
if(eregi("<title>(.+)
</title>",$data,$m)){
$title=$m["1"];
}
else{
$title="no title";
}
$array[]="$dir/$file $title";
}
2,Add links to searching results
CHANGE THE FOLLOWING
foreach($array as $value){
echo "$value"."
\n";
}
TO
foreach($array as $value){
list($filedir,$title)=split("[ ]",$value,"2");
echo "$value"."
\n";
}
3 Set time limit for PHP execution
ADD THE FOLLOWING AT THE BEGINNING OF PHP FILES
set_time_limit("600");
The above unit is second，so ten minutes is the litmit.
Now, combine all the above programs and get the complete search.php file as following,
<?php
set_time_limit("600");
$keyword=trim($_POST["keyword"]);
if($keyword==""){
echo"Please enter your keyword";
exit; }
function listFiles($dir,$keyword,&$array){
$handle=opendir($dir);
while(false!==($file=readdir($handle))){
if($file!="."&&$file!=".."){
if(is_dir("$dir/$file")){
listFiles("$dir/$file",$keyword,$array);
}
else{
$data=fread(fopen("$dir/$file","r"),filesize("$dir/$file"));
if(eregi("<body([^>]+)>(.+)</body>",$data,$b)){
$body=strip_tags($b["2"]);
}
else{
$body=strip_tags($data);
} if($file!="search.php"){
if(eregi("$keyword",$body)){
if(eregi("<title>(.+)</title>",$data,$m)){
$title=$m["1"];
}
else{
$title="no title";
}
$array[]="$dir/$file $title";
}
}
}
}
}
}
$array=array();
listFiles(".","$keyword",$array);
foreach($array as $value){
list($filedir,$title)=split("[ ]",$value,"2");
echo "$title "."
\n";
} ?>
Now, you have made a search engine for your website, enjoy it!
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