生成簽名，隨機字符串，XML轉爲數組，數組轉XML，json封裝，獲取IP地址

/*
 * ******生成簽名*********
 */
private function getSign($params)
{
    ksort($params); //將參數數組按照參數名ASCII碼從小到大排序
    foreach ($params as $key => $item) {
        if (!empty($item)) {  //剔除參數值爲空的參數
            $newArr[] = $key . '=' . $item; // 整合新的參數數組
        }
    }
    $stringA = implode("&", $newArr);  //使用 & 符號鏈接參數
    $stringSignTemp = $stringA . "&key=" . "key";
    // key是在商戶平臺API安全裏本身設置的
    $stringSignTemp = hash_hmac("sha256",$stringSignTemp,"key"); //將字符串進行MD5加密或hash_hmac加密
    $sign = strtoupper($stringSignTemp); //將全部字符轉換爲大寫
    return $sign;
}

/*
* ***生成隨機字符串*****
*/
function rand_code()
{
    $str = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';//62個字符
    $str = str_shuffle($str);
    $str = substr($str, 0, 32);
    return $str;
}

/*
 * ******傳輸給微信的參數要組成xml格式發送，傳入參數數組
*/
public function ToXml($data = array())
{
    if (!is_array($data) || count($data) <= 0) {
        return '數組異常';
    }
    $xml = "<xml>";
    foreach ($data as $key => $val) {
        if (is_numeric($val)) {
            $xml .= "<" . $key . ">" . $val . "</" . $key . ">";
        } else {
            $xml .= "<" . $key . "><![CDATA[" . $val . "]]></" . $key . ">";
        }
    }
    $xml .= "</xml>";
    return $xml;
}

/*
 * ******將xml數據轉換爲數組，接收微信返回數據時用到*********
 */
public function FromXml($xml)
{
    if (!$xml) {
        echo "xml數據異常！";
    }
    //將XML轉爲array
    //禁止引用外部xml實體
    libxml_disable_entity_loader(true);
    $data = json_decode(json_encode(simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA)), true);

    return $data;
}

/**
 * api 數據返回
 * @param  [int] $code [結果碼 200:正常/4**數據問題/5**服務器問題]
 * @param  [string] $msg  [接口要返回的提示信息]
 * @param  [array]  $data [接口要返回的數據]
 * @return [string]       [最終的json數據]
 */

 function return_msg($code, $msg = '', $data = []) {
        /*********** 組合數據  ***********/
        $return_data['code'] = $code;
        $return_data['msg']  = $msg;
        if(empty($data)){
            $return_data['data'] = "";
        }else{
            $return_data['data'] = $data;
        }
        /*********** 返回信息並終止腳本  ***********/
//        echo json_encode($return_data,JSON_UNESCAPED_UNICODE);die;
        echo str_replace(':null',':""',json_encode($return_data,JSON_UNESCAPED_UNICODE));die;//JSON_UNESCAPED_UNUCODE 禁止中文轉換
    }

/* * 獲取當前用戶註冊的ip */function get_client_ip($type = 0){    $type = $type ? 1 : 0;    static $ip = NULL;    if ($ip !== NULL) return $ip[$type];    if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {        $arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);        $pos = array_search('unknown', $arr);        if (false !== $pos) unset($arr[$pos]);        $ip = trim($arr[0]);    } elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {        $ip = $_SERVER['HTTP_CLIENT_IP'];    } elseif (isset($_SERVER['REMOTE_ADDR'])) {        $ip = $_SERVER['REMOTE_ADDR'];    }    // IP地址合法驗證    $long = sprintf("%u", ip2long($ip));    $ip = $long ? array($ip, $long) : array('0.0.0.0', 0);    return $ip[$type];}