card/merchant/controller/Login.php

 <?php
session_start();
include_once("../../untils/conn.php");
mysqli_query($con, "set names utf8");

// 判断session中是否存在账号信息
if (isset($_SESSION["account"])) {
    $proxy_acc = mysqli_real_escape_string($con, $_SESSION["account"]);
    $sql = "select proxy_acc,proxy_pass from proxy where proxy_acc='$proxy_acc';";
    $result = mysqli_query($con, $sql);
    $row = mysqli_num_rows($result);
    if ($row) {
        echo json_encode([
            "code" => 2,
            "msg" => '已登录',
            "data" => $_SESSION["account"]
        ]);
        exit;
    }
}

// 判断账号和密码是否都已输入
if (empty($_POST['account']) || empty($_POST['password'])) {
    echo json_encode([
        "code" => 401,
        "msg" => '请输入账号和密码',
    ]);
    exit;
}

$proxy_acc = mysqli_real_escape_string($con, $_POST['account']);
$proxy_pass = mysqli_real_escape_string($con, $_POST['password']);

$sql = "select proxy_acc,proxy_pass,proxy_sta,state_ban from proxy where proxy_acc='$proxy_acc';";
$result = mysqli_query($con, $sql);
$row = mysqli_fetch_assoc($result);

// 判断账号是否存在
if (!$row) {
    echo json_encode([
        "code" => 400,
        "msg" => '账号不存在',
    ]);
    exit;
}


if ($row['proxy_sta'] == 0) {
    echo json_encode([
        "code" => 400,
        "msg" => "您的账号已被封禁!请联系平台客服处理！\n封禁原因：" . $row['state_ban'],
    ]);
    exit;
}



// 验证密码
if ($row['proxy_pass'] != $proxy_pass) {
    echo json_encode([
        "code" => 400,
        "msg" => '账号密码错误',
    ]);
    exit;
}

// 登录成功
$_SESSION["account"] = $proxy_acc;
echo json_encode([
    "code" => 200,
    "msg" => '登录成功',
]);

?>