php生成短网址/短链接原理和用法实例分析

<?php
header("Content-type:application/json");

//GET URL
$url = $_GET["url"];

//过滤数据
if (trim(empty($url))) {
  echo "{\"code\":\"1\",\"url\":\"未传入URL\"}";
}else{
  //定义数据库配置
  $dbhost = "xxx";//数据库服务器地址
  $dbuser = "xxx";//数据库账号
  $dbpwd = "xxx";//数据库密码
  $dbname = "xxx";//数据库名

  //连接数据库
  $con = mysql_connect($dbhost,$dbuser,$dbpwd);
  if (!$con)
   {
   die('Could not connect: ' . mysql_error());
   }
  mysql_select_db($dbname, $con);

  //检查数据库是否已经存在该URL
  $check = mysql_query("SELECT * FROM 表名 WHERE long_url = '$url'");
  $check_result = mysql_num_rows($check);
  //如果已经存在，则直接返回之前生成的链接
  if ($check_result) {
    while ($row_yicunzai = mysql_fetch_array($check)) {
      $yicunzai_key = $row_yicunzai["dwz_key"];
      //返回KEY
      echo "{\"code\":\"0\",\"url\":\"域名".$yicunzai_key."\"}";
    }
  }else{
    //生成KEY
    $key_str = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
    $key = substr(str_shuffle($key_str),mt_rand(0,strlen($key_str)-11),4);

    //生成短链接
    mysql_query("INSERT INTO lkydwz (long_url, dwz_key) VALUES ('$url', '$key')");

    //返回结果
    echo "{\"code\":\"0\",\"url\":\"域名".$key."\"}";
  }

  //断开数据库连接
  mysql_close($con);
}

?>

<?php
header("Content-Type:text/html;charset=utf-8");
//获得当前传过来的KEY
$key = $_GET["id"];
echo "<title>正在跳转</title>";
//过滤数据
if (trim(empty($key))) {
  echo "链接不存在";
}else{
  //解析KEY
  //定义数据库配置
  $dbhost = "xxx";//数据库服务器地址
  $dbuser = "xxx";//数据库账号
  $dbpwd = "xxx";//数据库密码
  $dbname = "xxx";//数据库名
  //连接数据库
  $con = mysql_connect($dbhost,$dbuser,$dbpwd);
  if (!$con)
   {
   die('Could not connect: ' . mysql_error());
   }
  mysql_select_db($dbname, $con);

  //查询数据库，通过KEY获取长链接进行跳转
  //检查数据库是否存在该KEY
  $check = mysql_query("SELECT * FROM 表名 WHERE dwz_key = '$key'");
  $check_result = mysql_num_rows($check);
  //如果存在，则解析出长链接并跳转
  if ($check_result) {
    while ($row_long_url = mysql_fetch_array($check)) {
      $long_url = $row_long_url["long_url"];
      // echo "<script>location.href=\"".$long_url."\";</script>";
      header("Location: $long_url");
    }
  }else{
    echo "链接不存在";
  }
}
?>

RewriteEngine On
#RewriteBase / 
RewriteRule ^(\w+)$ index.php?id=$1

id(int)自增
dwz_key(varchar)
long_url(text)
creat_time(TIMESTAMP)

{"code":"0","url":"http://xxx.cn/Hp8R"}