原生php实现更新接口

-- phpMyAdmin SQL Dump
-- version 4.5.1
-- http://www.phpmyadmin.net
--
-- Host: 127.0.0.1
-- Generation Time: 2022-04-05 10:24:07
-- 服务器版本： 10.1.13-MariaDB
-- PHP Version: 5.6.21
SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";
/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8mb4 */;
--
-- Database: `a`
--
-- --------------------------------------------------------
--
-- 表的结构 `login`
--
CREATE TABLE `login` (
  `id` int(11) NOT NULL,
  `username` varchar(100) COLLATE utf8_vietnamese_ci NOT NULL COMMENT '用户名',
  `password` varchar(100) COLLATE utf8_vietnamese_ci NOT NULL COMMENT '密码'
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_vietnamese_ci;
--
-- 转存表中的数据 `login`
--
INSERT INTO `login` (`id`, `username`, `password`) VALUES
(50, 'cyg', '123456'),
(51, 'admin', '123456'),
(52, 'admin', '123456'),
(53, 'admin', '123456'),
(54, 'admin', '123456'),
(55, 'admin', '123456666');
--
-- Indexes for dumped tables
--
--
-- Indexes for table `login`
--
ALTER TABLE `login`
  ADD PRIMARY KEY (`id`);
--
-- 在导出的表使用AUTO_INCREMENT
--
--
-- 使用表AUTO_INCREMENT `login`
--
ALTER TABLE `login`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=56;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

<?php
$link=mysqli_connect('localhost','root','','a');
//然后是指定php链接数据库的字符集
mysqli_set_charset($link,'utf8');
if(!$_POST['username']||!$_POST['password'])
{
  exit();
}
if(!$_POST['id'])
{
  exit();
}
$username=$_POST['username'];
$password=$_POST['password'];
$id=$_POST['id'];
$sql = "UPDATE login set username='$username',password='$password' where  id='$id'";//运行sql
$result=mysqli_query($link,$sql);//运行sql
if($result)
{
  $sql="select * from login where id='$id'";
  $result=mysqli_query($link,$sql);//运行sql
}
if(mysqli_num_rows($result) > 0){
  while($row = mysqli_fetch_assoc($result)) {
    $data[] = $row;
    }
    $json = json_encode(array(
            "resultCode"=>200,
            "message"=>"新增成功！",
            "data"=>$data
        ),JSON_UNESCAPED_UNICODE);
        //转换成字符串JSON
        echo($json);
}else{
     $json = json_encode(array(
            "resultCode"=>200,
            "message"=>"暂无数据",
            "data"=>''
        ),JSON_UNESCAPED_UNICODE);
        //转换成字符串JSON
        echo($json);
}
?>