```
<?php
// 验证
$data = $_REQUEST;
$sign = '';
ksort($data);
foreach ($data as $k => $v) {
if($v && $k !== 'sign' && $k !== 'sign_type') $sign .= $k . '=' . $v . '&';
}
$sign = md5(rtrim($sign, '&') . '你的KEY');
if($sign == $data['sign']) {
// 验签成功！
}
// 发起
$param = [
'pid'=>'123456',
'name'=>'cs',
'type'=>'alipay',
'money'=>'0.01',
'out_trade_no'=>'123456',
'notify_url'=>'https://api.fcypay.cn',
'return_url'=>'https://api.fcypay.cn',
'sitename'=>'123456',
'sign_type'=>'MD5',
];
$key = '123456';
$url = 'https://api.fcypay.cn/api/payment';
ksort($param);
$sign = '';
foreach ($param as $k => $v) {
if($v && $k !== 'sign' && $k !== 'sign_type'){
$sign.=$k.'='.$v.'&';
}
}
$sign = trim($sign,'&');
$param['sign'] = md5($sign.$key);
```
