<?php
namespace app\index\controller;

class Index
{
    public function index()
    {
        if (isset($_GET['echostr'])) {
            //获得参数 signature nonce token timestamp echostr
            $nonce = $_GET['nonce'];
            $token = 'weixin';
            $timestamp = $_GET['timestamp'];
            $echostr = $_GET['echostr'];
            $signature = $_GET['signature'];
            //形成数组，然后按字典序排序
            $array = array();
            $array = array($nonce, $timestamp, $token);
            sort($array);
            //拼接成字符串,sha1加密 ，然后与signature进行校验
            $str = sha1(implode($array));
            if ($str == $signature && $echostr) {
                //第一次接入weixin api接口的时候
                echo $echostr;
                exit;
            }
        } else {
            $this->responseMsg();
        }
    }

    public function responseMsg(){
        //1.获取微信推送过来的post数据(xml格式)
        $postArr = file_get_contents("php://input");
        libxml_disable_entity_loader(true);
        $postObj = simplexml_load_string($postArr, 'SimpleXMLElement', LIBXML_NOCDATA);
//        print_r($postObj);
        if(strtolower($postObj->MsgType) == 'event'){
            if(strtolower($postObj->Event) == 'subscribe'){
                $toUser = $postObj->FromUserName;
                $fromUser = $postObj->ToUserName;
                $time = time();
                $msgType = 'text';
                $content = '欢迎关注我们的微信公众号';
                $template = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[%s]]></MsgType>
                    <Content><![CDATA[%s]]></Content>
                    </xml>";
                $info = sprintf($template,$toUser,$fromUser,$time,$msgType,$content);

                echo $info;
            }
        }

    }
    
    本人用的tp5框架