paypal php 对接

<form id="form_starPay" name="form_starPay" action="https://www.sandbox.paypal.com/cgi-bin/webscr" method="post">
<input type="hidden" name="cmd" value="_xclick"> //告诉paypal该表单是立即购买
<input type="hidden" name="business" value="XXXXXX@XXXXX.com"> //卖家帐号  也就是收钱的帐号
<input type="hidden" name="item_name" value="name"> //商品名称
<input type="hidden" name="amount" value="10000"> //价格
<input type="hidden" name="currency_code" value="JPY"> //币种
<input type="hidden" name="return" value="http://localhost/frontend/pay/PDT_order"> //支付成功后网页跳转地址
<input type="hidden" name="notify_url" value="http://localhost/frontend/pay/IPN_Order"> //支付成功后paypal后台发送订单通知地址
<input type="hidden" name="invoice" value=""> //自定义订单号   paypal原样返回
<input type="hidden" name="custom" value=""> // 自定义变量  paypal原样返回
<input type="hidden" name="lc" value="JP"> //支付页面语言设置
<input style="visibility:hidden" type="image" src=" https://www.paypal.com/en_US/i/btn/btn_buynow_LG.gif " border="0" name="submit" alt=" PayPal - The safer, easier way to pay online">//支付按钮

</form>

<?php 
//获取 PayPal 交易流水号 tx 
$tx_token = $_GET['tx']; 
//定义您的身份标记 
$auth_token = "CHANGE-TO-YOUR-TOKEN"; 
//形成验证字符串 
$req = " cmd=_notify-synch&tx=$tx_token&at=$auth_token"; 
//将交易流水号及身份标记返回 PayPal 验证 
$header .= "POST /cgi-bin/webscr HTTP/1.0\r\n"; 
$header .= "Content-Type: application/x-www-form-urlencoded\r\n"; 
$header .= "Content-Length: " . strlen($req) . "\r\n\r\n"; 
$fp = fsockopen ('www.paypal.com', 80, $errno, $errstr, 30); 
if (!$fp) { 
// HTTP ERROR 
} else { 
fputs ($fp, $header . $req); 
//获取返回数据 
$res = ''; 
$headerdone = false; 
while (!feof($fp)) { 
$line = fgets ($fp, 1024); 
if (strcmp($line, "\r\n") == 0) { 
//获取头 
$headerdone = true; 
}else if ($headerdone){ 
//获取主体内容 
$res .= $line; 
} 
} 
//解析获取内容 
$lines = explode("\n", $res); 
$keyarray = array(); 
if (strcmp ($lines[0], "SUCCESS") == 0) { 
for ($i=1; $i<count($lines);$i++){ 
list($key,$val) = explode("=", $lines[$i]); 
$keyarray[urldecode($key)] = urldecode($val); 
} 
//检查交易付款状态 payment_status 是否为  „Completed‟ 
//检查交易流水号 txn_id 是否已经被处理过 
//检查接收 EMAIL receiver_email 是否为您的 PayPal 中已经注册的 EMAIL 
//检查金额 mc_gross 是否正确 
//…… 
//处理此次付款明细 
//该付款明细所有变量可参考： 
//https://www.paypal.com/IntegrationCenter/ic_ipn-pdt-variable-reference.html 
$name = $keyarray['first_name'] . ' ' . $keyarray['last_name']; 
$itemname = $keyarray['item_name']; 
$amount = $keyarray['mc_gross']; 
echo ("<p><h3>Thank you for you purchase!</h3></p>"); 
echo ("<b>Payment Details:</b><br>\n"); 
echo ("<li>Name: $name</li>\n"); 
echo ("<li>Item: $itemname</li>\n"); 
echo ("<li>Amount: $amount</li>\n"); 
}else if (strcmp ($lines[0], "FAIL") == 0) { 
//获取付款明细失败，记录并检查 
} 
} 
fclose ($fp); 
?> 

<?php 
//从 PayPal 出读取 POST 信息同时添加变量„cmd‟ 
$req = 'cmd=_notify-validate'; 
foreach ($_POST as $key => $value) { 
$value = urlencode(stripslashes($value)); 
$req .= "&$key=$value"; 
} 
//建议在此将接受到的信息记录到日志文件中以确认是否收到 IPN 信息 
//将信息 POST 回给 PayPal 进行验证 
$header .= "POST /cgi-bin/webscr HTTP/1.0\r\n"; 
$header .= "Content-Type:application/x-www-form-urlencoded\r\n"; 
$header .= "Content-Length:" . strlen($req) ."\r\n\r\n"; 
//在 Sandbox 情况下，设置： 
//$fp = fsockopen(„www.sandbox.paypal.com‟,80,$errno,$errstr,30); 
$fp = fsockopen ('www.paypal.com', 80, $errno, $errstr, 30); 
//将 POST 变量记录在本地变量中 
//该付款明细所有变量可参考： 
//https://www.paypal.com/IntegrationCenter/ic_ipn-pdt-variable-reference.html 
$item_name = $_POST['item_name']; 
$item_number = $_POST['item_number']; 
$payment_status = $_POST['payment_status']; 
$payment_amount = $_POST['mc_gross']; 
$payment_currency = $_POST['mc_currency']; 
$txn_id = $_POST['txn_id']; 
$receiver_email = $_POST['receiver_email']; 
$payer_email = $_POST['payer_email']; 
//… 
//判断回复 POST 是否创建成功 
if (!$fp) { 
//HTTP 错误 
}else { 
//将回复 POST 信息写入 SOCKET 端口 
fputs ($fp, $header .$req); 
//开始接受 PayPal 对回复 POST 信息的认证信息 
while (!feof($fp)) { 
$res = fgets ($fp, 1024); 
//已经通过认证 
if (strcmp ($res, "VERIFIED") == 0) { 
//检查付款状态 
//检查 txn_id 是否已经处理过 
//检查 receiver_email 是否是您的 PayPal 账户中的 EMAIL 地址 
//检查付款金额和货币单位是否正确 
//处理这次付款，包括写数据库 
}else if (strcmp ($res, "INVALID") == 0) { 
//未通过认证，有可能是编码错误或非法的 POST 信息 
} 
} 
fclose ($fp); 
} 
?>