网上的很多php支付宝支付接入教程都颇为复杂，且需要配置和引入较多的文件，本人通过整理后给出一个单文件版的，希望可以给各位想接入支付宝支付的带来些许帮助和借鉴意义。
推荐：《PHP视频教程》
一个PHP文件搞定支付宝系列：https://github.com/dedemao/alipay
一个PHP文件搞定微信支付系列：https://github.com/dedemao/weixinPay
在手机浏览器下打开实现效果
立即学习“PHP免费学习笔记（深入）”；
在微信中打开实现效果
注：兼容微信浏览器需依赖支付宝官方提供的demo（alipay_in_weixin_demo）中的两个文件，即：ap.js及pay.htm
环境依赖
PHP5.0以上，且需要开启CURL服务、SSL服务。
如需兼容微信浏览器，还需依赖ap.js及pay.htm。
注意事项
1.文件开头的配置信息必须完善
2.商户私钥需填写对应签名算法类型的私钥，如何生成密钥参考：
2.1 https://docs.open.alipay.com/291/105971
2.2 https://docs.open.alipay.com/200/105310
代码
<?php
header('Content-type:text/html; Charset=utf-8');
$appid = 'xxxxx'; //https://open.alipay.com 账户中心->密钥管理->开放平台密钥，填写添加了电脑网站支付的应用的APPID
$returnUrl = 'http://www.xxx.com/alipay/return.php'; //付款成功后的同步回调地址
$notifyUrl = 'http://www.xxx.com/alipay/notify.php'; //付款成功后的异步回调地址
$outTradeNo = uniqid(); //你自己的商品订单号
$payAmount = 0.01; //付款金额，单位:元
$orderName = '支付测试'; //订单标题
$signType = 'RSA2'; //签名算法类型，支持RSA2和RSA，推荐使用RSA2
//商户私钥，填写对应签名算法类型的私钥，如何生成密钥参考：https://docs.open.alipay.com/291/105971和https://docs.open.alipay.com/200/105310
$saPrivateKey='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';
$aliPay = new AlipayService($appid,$returnUrl,$notifyUrl,$saPrivateKey);
$payConfigs = $aliPay->doPay($payAmount,$outTradeNo,$orderName,$returnUrl,$notifyUrl);
class AlipayService
{
protected $appId;
protected $returnUrl;
protected $notifyUrl;
protected $charset;
//私钥值
protected $rsaPrivateKey;
public function __construct($appid, $returnUrl, $notifyUrl,$saPrivateKey)
{
$this->appId = $appid;
$this->returnUrl = $returnUrl;
$this->notifyUrl = $notifyUrl;
$this->charset = 'utf8';
$this->rsaPrivateKey=$saPrivateKey;
}
/**
* 发起订单
* @param float $totalFee 收款总费用 单位元
* @param string $outTradeNo 唯一的订单号
* @param string $orderName 订单名称
* @param string $notifyUrl 支付结果通知url 不要有问号
* @param string $timestamp 订单发起时间
* @return array
*/
public function doPay($totalFee, $outTradeNo, $orderName, $returnUrl,$notifyUrl)
{
//请求参数
$requestConfigs = array(
'out_trade_no'=>$outTradeNo,
'product_code'=>'QUICK_WAP_WAY',
'total_amount'=>$totalFee, //单位 元
'subject'=>$orderName, //订单标题
);
$commonConfigs = array(
//公共参数
'app_id' => $this->appId,
'method' => 'alipay.trade.wap.pay', //接口名称
'format' => 'JSON',
'return_url' => $returnUrl,
'charset'=>$this->charset,
'sign_type'=>'RSA2',
'timestamp'=>date('Y-m-d H:i:s'),
'version'=>'1.0',
'notify_url' => $notifyUrl,
'biz_content'=>json_encode($requestConfigs),
);
$commonConfigs["sign"] = $this->generateSign($commonConfigs, $commonConfigs['sign_type']);
return $commonConfigs;
}
public function generateSign($params, $signType = "RSA") {
return $this->sign($this->getSignContent($params), $signType);
}
protected function sign($data, $signType = "RSA") {
$priKey=$this->rsaPrivateKey;
$res = "-----BEGIN RSA PRIVATE KEY-----\n" .
wordwrap($priKey, 64, "\n", true) .
"\n-----END RSA PRIVATE KEY-----";
($res) or die('您使用的私钥格式错误，请检查RSA私钥配置');
if ("RSA2" == $signType) {
openssl_sign($data, $sign, $res, version_compare(PHP_VERSION,'5.4.0', '<') ? SHA256 : OPENSSL_ALGO_SHA256); //OPENSSL_ALGO_SHA256是php5.4.8以上版本才支持
} else {
openssl_sign($data, $sign, $res);
}
$sign = base64_encode($sign);
return $sign;
}
/**
* 校验$value是否非空
* if not set ,return true;
* if is null , return true;
**/
protected function checkEmpty($value) {
if (!isset($value))
return true;
if ($value === null)
return true;
if (trim($value) === "")
return true;
return false;
}
public function getSignContent($params) {
ksort($params);
$stringToBeSigned = "";
$i = 0;
foreach ($params as $k => $v) {
if (false === $this->checkEmpty($v) && "@" != substr($v, 0, 1)) {
// 转换成目标字符集
$v = $this->characet($v, $this->charset);
if ($i == 0) {
$stringToBeSigned .= "$k" . "=" . "$v";
} else {
$stringToBeSigned .= "&" . "$k" . "=" . "$v";
}
$i++;
}
}
unset ($k, $v);
return $stringToBeSigned;
}
/**
* 转换字符集编码
* @param $data
* @param $targetCharset
* @return string
*/
function characet($data, $targetCharset) {
if (!empty($data)) {
$fileType = $this->charset;
if (strcasecmp($fileType, $targetCharset) != 0) {
$data = mb_convert_encoding($data, $targetCharset, $fileType);
}
}
return $data;
}
}
function isWeixin(){
if ( strpos($_SERVER['HTTP_USER_AGENT'],'MicroMessenger') !== false ) {
return true;
}
return false;
}
$queryStr = http_build_query($payConfigs);
if(isWeixin()):
?>
<script type="text/javascript" src="ap.js"></script>
<script>
var gotoUrl = 'https://openapi.alipay.com/gateway.do?<?=$queryStr?>';
_AP.pay(gotoUrl);
</script>
<?php
else:
header("Location:https://openapi.alipay.com/gateway.do?{$queryStr}");
endif;
?> 
