yhq-smallapp/app/Support/helpers.php

<?php

if (!function_exists('get_client_code_version')) {
    /**
     * 读取客户端代码版本号，用于客户端自动加载新提交的代码
     * @return string
     */
    function get_client_code_version()
    {
        // 前端版本号文件路径
        $versionFile = public_path('version.md');

        // 文件存在，且有读权限
        if (file_exists($versionFile) && is_readable($versionFile)) {
            $version = @file_get_contents($versionFile);
            if ($version) {
                return trim($version);
            }
        }

        return false;
    }
}


if (!function_exists('check_signature')) {
    /**
     * 校验用户签名
     * @return string
     */
    function check_signature($params, $token)
    {
        // 按数组键名 正序排序
        ksort($params);
        $tem = array();
        foreach ($params as $k => $v) {
            if ($k !== 'sign') {
                $tem[] = "$k=$v";
            }
        }
        $sk = implode('&', $tem);
        return (md5($sk) == $token);
    }
}

if (!function_exists('get_random')) {
    /**
     * 生成随机字符串
     * @return string
     */
    function get_random($length = 6, $type = 'string', $convert = 0)
    {
        $config = array(
            'number' => '1234567890',
            'letter' => 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
            'string' => 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKMNPQRSTUVWXYZ23456789',
            'all' => 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890'
        );

        if (!isset($config[$type]))
            $type = 'string';
        $string = $config[$type];

        $code = '';
        $strlen = strlen($string) - 1;
        for ($i = 0; $i < $length; $i++) {
            $code .= $string[mt_rand(0, $strlen)];
        }

        if (!empty($convert)) {
            $code = ($convert > 0) ? strtoupper($code) : strtolower($code);
        }
        return $code;
    }
}