关注事件与一般的文本消息有两处不同，一是MsgType值是event，二是增加了Event值是subscribe。由于官方文档（最初的wx_sample.php）没有提取这个参数，需要我们自己提取。在程序中增加两个变量$msgType和$event。
<?php /** * wechat php test */ //define your token define("TOKEN", "weixin"); $wechatObj = new wechatCallbackapiTest(); //$wechatObj->valid();//接口验证 $wechatObj->responseMsg();//调用回复消息方法 class wechatCallbackapiTest { public function valid() { $echoStr = $_GET["echostr"]; //valid signature , option if($this->checkSignature()){ echo $echoStr; exit; } } public function responseMsg() { //get post data, May be due to the different environments $postStr = $GLOBALS["HTTP_RAW_POST_DATA"]; //extract post data if (!empty($postStr)){ /* libxml_disable_entity_loader is to prevent XML eXternal Entity Injection, the best way is to check the validity of xml by yourself */ libxml_disable_entity_loader(true); $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA); $fromUsername = $postObj->FromUserName; $toUsername = $postObj->ToUserName; $keyword = trim($postObj->Content); $time = time(); $msgType = $postObj->MsgType;//消息类型 $event = $postObj->Event;//时间类型，subscribe（订阅）、unsubscribe（取消订阅） $textTpl = "<xml> <ToUserName><![CDATA[%s]]></ToUserName> <FromUserName><![CDATA[%s]]></FromUserName> <CreateTime>%s</CreateTime> <MsgType><![CDATA[%s]]></MsgType> <Content><![CDATA[%s]]></Content> <FuncFlag>0</FuncFlag> </xml>"; switch($msgType){ case "event": if($event=="subscribe"){ $contentStr = "Hi,欢迎关注海仙日用百货!"."\n"."回复数字'1',了解店铺地址."."\n"."回复数字'2',了解商品种类."; } break; case "text": switch($keyword){ case "1": $contentStr = "店铺地址："."\n"."杭州市江干艮山西路233号新东升市场地下室第一排."; break; case "2": $contentStr = "商品种类:"."\n"."杯子、碗、棉签、水桶、垃圾桶、洗碗巾(刷)、拖把、扫把、" ."衣架、粘钩、牙签、垃圾袋、保鲜袋(膜)、剪刀、水果刀、饭盒等."; break; default: $contentStr = "对不起,你的内容我会稍后回复"; } break; } $msgType = "text"; $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr); echo $resultStr; }else { echo ""; exit; } } private function checkSignature() { // you must define TOKEN by yourself if (!defined("TOKEN")) { throw new Exception('TOKEN is not defined!'); } $signature = $_GET["signature"]; $timestamp = $_GET["timestamp"]; $nonce = $_GET["nonce"]; $token = TOKEN; $tmpArr = array($token, $timestamp, $nonce); // use SORT_STRING rule sort($tmpArr, SORT_STRING); $tmpStr = implode( $tmpArr ); $tmpStr = sha1( $tmpStr ); if( $tmpStr == $signature ){ return true; }else{ return false; } } } ?>