PHP function to obtain search engine inbound keywords

This article introduces a piece of code that can obtain search engine inbound keywords. Friends in need can refer to it.

The code is as follows:

<?php
//*
* 获取来自搜索引擎入站关键词
* edit by bbs.it-home.org
*/
function get_keyword($url,$kw_start)//函数作用：从url中提取关键词。参数说明：url及关键词前的字符。
{
 $start=stripos($url,$kw_start);
 $url=substr($url,$start+strlen($kw_start));
 $start=stripos($url,'&');
  if ($start>0)
  {
   $start=stripos($url,'&');
   $s_s_keyword=substr($url,0,$start);
  }
  else 
  {
  $s_s_keyword=substr($url,0);
  }
 return $s_s_keyword;
}
$url=isset($_SERVER['HTTP_REFERER'])?$_SERVER['HTTP_REFERER']:'';//获取入站url。
$search_1="google.com"; //q=
$search_2="baidu.com"; //wd=

$google=preg_match("/\b{$search_1}\b/",$url);//记录匹配情况，用于入站判断。
$baidu=preg_match("/\b{$search_2}\b/",$url);
$s_s_keyword="";
 if ($google)
 {//来自google
  $s_s_keyword=get_keyword($url,'q=');//关键词前的字符为“q=”。
  $s_s_keyword=urldecode($s_s_keyword);
  //$s_s_keyword=iconv("GBK","UTF-8",$s_s_keyword);//引擎为gbk
 }
 else if($baidu)
 {//来自百度
  $s_s_keyword=get_keyword($url,'wd=');//关键词前的字符为“wd=”。
  $s_s_keyword=urldecode($s_s_keyword);
  $s_s_keyword=iconv("GBK","UTF-8",$s_s_keyword);//引擎为gbk
 }
 
echo '$s_s_keyword';
?>

Code description: 1. Pay attention to the problem of character encoding, because different search engines may return different encoding formats. 2. For a more comprehensive function, please refer to this article: Obtain search engine keyword sources.