在这篇微信公众平台开发教程中，我们将介绍如何使用开发模式实现多客服系统。

本文分为以下三个部分：回复多客服消息

触发多客服会话

其他说明

一、回复多客服消息

在新的微信协议中，开发模式也可以接入客服系统。 开发者如果需要让用户使用客服系统，需要在接收到用户发送的消息时，返回一个MsgType为transfer_customer_service的消息，微信服务器在收到这条消息时，会把用户这次发送的和以后一段时间内发送的消息转发客服系统。

返回的消息举例如下

1399197672

该消息的实现如下//回复多客服消息

private function transmitService($object)

{

$xmlTpl = "

%s

";

$result = sprintf($xmlTpl, $object->FromUserName, $object->ToUserName, time());

return $result;

}

二、触发多客服会话

一般情况下，用户想要咨询问题是，经常会问“你好”，“在吗”，这样的问题。

我们以这些词为触发关键词，当用户发送的文本消息内容中包含这些词的时候，就返回多客服消息给用户(用户在微信端感觉不到任何内容，但微信公众账号会将用户本次及以后一段时间的消息都转发到客服)。

实现代码如下：//接收文本消息

private function receiveText($object)

{

$keyword = trim($object->Content);

if (strstr($keyword, "投诉") || strstr($keyword, "你好") || strstr($keyword, "在吗")){

$result = $this->transmitService($object);

}

return $result;

}

三、完整代码<?php

/*

方倍工作室

CopyRight 2014 All Rights Reserved

*/

define("TOKEN", "weixin");

$wechatObj = new wechatCallbackapiTest();

if (!isset($_GET['echostr'])) {

$wechatObj->responseMsg();

}else{

$wechatObj->valid();

}

class wechatCallbackapiTest

{

//验证消息

public function valid()

{

$echoStr = $_GET["echostr"];

if($this->checkSignature()){

echo $echoStr;

exit;

}

}

//检查签名

private function checkSignature()

{

$signature = $_GET["signature"];

$timestamp = $_GET["timestamp"];

$nonce = $_GET["nonce"];

$token = TOKEN;

$tmpArr = array($token, $timestamp, $nonce);

sort($tmpArr, SORT_STRING);

$tmpStr = implode($tmpArr);

$tmpStr = sha1($tmpStr);

if($tmpStr == $signature){

return true;

}else{

return false;

}

}

//响应消息

public function responseMsg()

{

$postStr = $GLOBALS["HTTP_RAW_POST_DATA"];

if (!empty($postStr)){

$this->logger("R ".$postStr);

$postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);

$RX_TYPE = trim($postObj->MsgType);

switch ($RX_TYPE)

{

case "event":

$result = $this->receiveEvent($postObj);

break;

case "text":

$result = $this->receiveText($postObj);

break;

}

$this->logger("T ".$result);

echo $result;

}else {

echo "";

exit;

}

}

//接收事件消息

private function receiveEvent($object)

{

switch ($object->Event)

{

case "subscribe":

$content[] = array("Title" =>"欢迎关注方倍工作室", "Description" =>"使用方法：\n1.发送快递单号,例如6367532560,可查询快递详情", "PicUrl" =>"http://www.3856.cc/weixin/weixin/logo.jpg", "Url" =>"");

break;

default:

$content = "receive a new event: ".$object->Event;

break;

}

if(is_array($content)){

if (isset($content[0])){

$result = $this->transmitNews($object, $content);

}else if (isset($content['MusicUrl'])){

$result = $this->transmitMusic($object, $content);

}

}else{

$result = $this->transmitText($object, $content);

}

return $result;

}

//接收文本消息

private function receiveText($object)

{

$keyword = trim($object->Content);

if($keyword == "时间" || $keyword == "测试"){

$content = date("Y-m-d H:i:s",time());

$result = $this->transmitText($object, $content);

}

//触发多客服模式

else if (strstr($keyword, "您好") || strstr($keyword, "你好") || strstr($keyword, "在吗") || strstr($keyword, "有人吗")){

$result = $this->transmitService($object);

return $result;

}

return $result;

}

private function transmitText($object, $content)

{

$textTpl = "

%s

";

$result = sprintf($textTpl, $object->FromUserName, $object->ToUserName, time(), $content);

return $result;

}

private function transmitNews($object, $newsArray)

{

if(!is_array($newsArray)){

return;

}

$itemTpl = "

";

$item_str = "";

foreach ($newsArray as $item){

$item_str .= sprintf($itemTpl, $item['Title'], $item['Description'], $item['PicUrl'], $item['Url']);

}

$newsTpl = "

%s

%s

$item_str

";

$result = sprintf($newsTpl, $object->FromUserName, $object->ToUserName, time(), count($newsArray));

return $result;

}

private function transmitMusic($object, $musicArray)

{

$itemTpl = "

";

$item_str = sprintf($itemTpl, $musicArray['Title'], $musicArray['Description'], $musicArray['MusicUrl'], $musicArray['HQMusicUrl']);

$textTpl = "

%s

$item_str

";

$result = sprintf($textTpl, $object->FromUserName, $object->ToUserName, time());

return $result;

}

//回复多客服消息

private function transmitService($object)

{

$xmlTpl = "

%s

";

$result = sprintf($xmlTpl, $object->FromUserName, $object->ToUserName, time());

return $result;

}

private function logger($log_content)

{

if(isset($_SERVER['HTTP_APPNAME'])){ //SAE

sae_set_display_errors(false);

sae_debug($log_content);

sae_set_display_errors(true);

}else if($_SERVER['REMOTE_ADDR'] != "127.0.0.1"){ //LOCAL

$max_size = 10000;

$log_filename = "log.xml";

if(file_exists($log_filename) and (abs(filesize($log_filename)) > $max_size)){unlink($log_filename);}

file_put_contents($log_filename, date('H:i:s')." ".$log_content."\r\n", FILE_APPEND);

}

}

}

?>

四、其他注意事项

1. 经测试，在自定义菜单中返回多客服消息，无法让用户进入多客服状态。

2. 使用多客服消息后，后续所有消息在一段时间内都将作为客服消息转发，原来的开发模式下的自动回复都将失效！！！