一步一步学swift之：自己写Api接口-PHP

想要自己一个人完成app，那么后台接口也必须自己动动手。不用担心，其实很简单的，给自己信心！
下面就以登录注册为例，做一个api接口

首先在mac上搭建PHP环境，下载 MAMP Pro for Mac 3.4 破解版：

http://www.ifunmac.com/2015/08/mamp-pro-3-4/
即可一键安装Apache/PHP/MySQL开发环境。简单吧。

有了环境就可以写代码了：

首先写一个Config.php （配置数据库）

 <?php

  //定义数据库连接所需的变量
  define("DB_HOST", "localhost");
  define("DB_USER", "root");
  define("DB_PASSWORD", "master12!");
  define("DB_DATABASE", "loginAPI");

 ?>

写一个DB_Connect.php（用于连接数据库）

 <?php

 class DB_Connect
 {
     public $con;

     function __construct()
     {

     }

     function __destruct()
     {
         // $this->close();
     }

     //连接数据库
     public function connect()
     {
         require_once 'include/Config.php';
         //连接mysql
         $this->con = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_DATABASE) or die(mysqli_error($this->con));
         if (mysqli_connect_errno()) {
             die("Database connection failed");
         }

         // 返回 database handler
         return $this->con;
     }

     //关闭数据连接
     public function close()
     {
         mysqli_close($this->con);
     }

 }

 ?>

再来一个：DB_Functions.php （用来封装 执行sql后 返回数据的方法）

 <?php

 class DB_Functions {

     private $db;

     // constructor
     function __construct() {
         require_once 'DB_Connect.php';
         // connecting to database
         $this->db = new DB_Connect();
         $this->db->connect();
     }

     // destructor
     function __destruct() {

     }

     /**
      * 添加用户信息
      */
     public function storeUser($name, $email, $password) {
         $uuid = uniqid('', true);
         $hash = $this->hashSSHA($password);
         $encrypted_password = $hash["encrypted"]; // 加密后的密文
         $salt = $hash["salt"]; // salt
         $result = mysqli_query($this->db->con,"INSERT INTO users(unique_id, name, email, encrypted_password, salt, created_at) VALUES('$uuid', '$name', '$email', '$encrypted_password', '$salt', NOW())");
         // 检查结果
         if ($result) {
             // 获取用户信息
             $uid = mysqli_insert_id($this->db->con); // 获取最新的id
             $result = mysqli_query($this->db->con,"SELECT * FROM users WHERE uid = $uid");
             //返回刚插入的用户信息
             return mysqli_fetch_array($result);
         } else {
             return false;
         }
     }

     /**
      * 通过email和password获取用户信息
      */
     public function getUserByEmailAndPassword($email, $password) {
         $result = mysqli_query($this->db->con,"SELECT * FROM users WHERE email = '$email'") or die(mysqli_connect_errno());
         // check for result
         $no_of_rows = mysqli_num_rows($result);
         if ($no_of_rows > 0) {
             $result = mysqli_fetch_array($result);
             $salt = $result['salt'];
             $encrypted_password = $result['encrypted_password'];
             $hash = $this->checkhashSSHA($salt, $password);
             // check for password
             if ($encrypted_password == $hash) {
                 return $result;
             }
         } else {
             return false;
         }
     }

     /**
      * 通过email判断用户是否存在
      */
     public function isUserExisted($email) {
         $result = mysqli_query($this->db->con,"SELECT email from users WHERE email = '$email'");
         $no_of_rows = mysqli_num_rows($result);
         if ($no_of_rows > 0) {
             // 用户存在
             return true;
         } else {
             //用户不存在
             return false;
         }
     }

     /**
      * 加密
      * @param password
      * returns salt and encrypted password
      */
     public function hashSSHA($password) {

         $salt = sha1(rand());
         $salt = substr($salt, 0, 10);
         $encrypted = base64_encode(sha1($password . $salt, true) . $salt);
         $hash = array("salt" => $salt, "encrypted" => $encrypted);
         return $hash;
     }

     /**
      * 解密
      * @param salt, password
      * returns hash string
      */
     public function checkhashSSHA($salt, $password) {

         $hash = base64_encode(sha1($password . $salt, true) . $salt);

         return $hash;
     }

 }

 ?>

在Index.php调用并输出返回值（这个文件地址就是接口的访问地址）

 <?php

 if (isset($_POST['tag']) && $_POST['tag'] != '') {
     // tag是接口请求时post的值（方法名称），用来区别调用方法
     $tag = $_POST['tag'];

     //引用DB_Functions.php
     require_once 'include/DB_Functions.php';
     $db = new DB_Functions();

     // 定义输入数组
     $response = array("tag" => $tag, "error" => FALSE);

     // 判断tag值
     if ($tag == 'login') {
         //获取login方法的post参数
         $email = $_POST['email'];
         $password = $_POST['password'];

         // 通过email 和password获取用户信息
         $user = $db->getUserByEmailAndPassword($email, $password);
         if ($user != false) {
             //找到用户信息
             $response["error"] = FALSE;
             $response["uid"] = $user["unique_id"];
             $response["user"]["name"] = $user["name"];
             $response["user"]["email"] = $user["email"];
             $response["user"]["created_at"] = $user["created_at"];
             $response["user"]["updated_at"] = $user["updated_at"];
             echo json_encode($response);
         } else {
             //没有找到用户信息
             //输出错误信息
             $response["error"] = TRUE;
             $response["error_msg"] = "帐号或密码不正确!";
             echo json_encode($response);
         }
     } else if ($tag == 'register') {
         //注册帐号
         $name = $_POST['name'];
         $email = $_POST['email'];
         $password = $_POST['password'];

         // 判断用户是否存在
         if ($db->isUserExisted($email)) {
             // 如果用户存在就返错误提示
             $response["error"] = TRUE;
             $response["error_msg"] = "用户已存在";
             echo json_encode($response);
         } else {
             // 新增用户
             $user = $db->storeUser($name, $email, $password);
             if ($user) {
                 //新增成功返回用户信息
                 $response["error"] = FALSE;
                 $response["uid"] = $user["unique_id"];
                 $response["user"]["name"] = $user["name"];
                 $response["user"]["email"] = $user["email"];
                 $response["user"]["created_at"] = $user["created_at"];
                 $response["user"]["updated_at"] = $user["updated_at"];
                 echo json_encode($response);
             } else {
                 // 新增失败，返回错误信息
                 $response["error"] = TRUE;
                 $response["error_msg"] = "服务器繁忙，操作失败";
                 echo json_encode($response);
             }
         }
     } else {
         // tag值无效时
         $response["error"] = TRUE;
         $response["error_msg"] = "未找到您要的方法";
         echo json_encode($response);
     }
 } else {
     $response["error"] = TRUE;
     $response["error_msg"] = "您的参数不正确!";
     echo json_encode($response);
 }
 ?>