PHP和UniApp实现数据的登录验证与单点登录

<?php
if($_SERVER['REQUEST_METHOD'] == 'POST'){
    // 获取POST数据
    $username = $_POST['username'];
    $password = $_POST['password'];
    
    // 连接数据库
    $conn = mysqli_connect('localhost', 'root', 'password', 'database_name');
    if(!$conn){
        echo "数据库连接失败";
        exit;
    }
    
    // 查询用户信息
    $sql = "SELECT * FROM user_info WHERE username = '$username' AND password = '$password'";
    $result = mysqli_query($conn, $sql);
    
    if(mysqli_num_rows($result)>0){
        echo "登录成功";
    }else{
        echo "用户名或密码错误";
    }
}
?>

<template>
    <view>
        <input type="text" v-model="username" placeholder="请输入用户名" />
        <input type="password" v-model="password" placeholder="请输入密码" />
        <button @tap="login">登录</button>
    </view>
</template>

<script>
    export default {
        data() {
            return {
                username: '',
                password: ''
            };
        },
        methods: {
            login() {
                uni.request({
                    url: 'http://localhost/login.php',
                    method: 'POST',
                    data: {
                        username: this.username,
                        password: this.password
                    },
                    success: (res) => {
                        if(res.data === '登录成功'){
                            uni.showToast({
                                title: '登录成功',
                                icon: 'success'
                            })
                            // 登录成功后的逻辑处理
                        }else{
                            uni.showToast({
                                title: '登录失败',
                                icon: 'none'
                            })
                        }
                    }
                });
            }
        }
    }
</script>

// 存储用户登录信息
uni.setStorageSync('isLogin', true);
uni.setStorageSync('username', this.username);

// 判断用户是否登录
if(uni.getStorageSync('isLogin')){
    // 已登录，执行相应操作
}else{
    // 未登录，跳转到登录页面
    uni.navigateTo({
        url: '/pages/login'
    });
}