才开始学习微信开发模式和PHP，在此记录以供后阅。

<?php
/**
 * wechat php test
 */

//define your token
define( "TOKEN", "weixin" );
$wechatObj = new wechatCallbackapiTest();
if ( !isset( $_GET['echostr'] ) ) {
    $wechatObj->responseMsg();
}else {
    $wechatObj->valid();
}
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 );
            $RX_TYPE = trim( $postObj->MsgType );
            switch ( $RX_TYPE ) {
            case "text":
                $resultStr = $this->receiveText( $postObj );
                break;
            case "event":
                $resultStr = $this->receiveEvent( $postObj );
                break;
            default:
                $resultStr = "";
                break;
            }
            echo $resultStr;
        } else {
            echo "";
            exit;
        }
    }

    private function receiveText( $object ) {
        $getkeyword = $object->Content;
        switch ( $getkeyword ) {
        case '产品':
            $funcFlag = 0;
            $contentStr = "产品链接:http://www.xxx.com/products/";
            $resultStr = $this->transmitText( $object, $contentStr, $funcFlag );
            break;
        case '新闻':
            $funcFlag = 0;
            $contentStr ="新闻链接:http://www.xxx.com/news/";
            $resultStr = $this->transmitText( $object, $contentStr, $funcFlag );
            break;
        case '方案':
            $funcFlag = 0;
            $contentStr ="方案链接:http://www.xxx.com/articles/";
            $resultStr = $this->transmitText( $object, $contentStr, $funcFlag );
            break;
        case '我们':
            $funcFlag = 0;
            $contentStr ="我们链接:http://www.xxx.com/culture/?type=detail&id=1";
            $resultStr = $this->transmitText( $object, $contentStr, $funcFlag );
            break;
        default:
            break;
        }

        return $resultStr;
    }

    private function receiveEvent( $object ) {
        $contentStr = "";
        switch ( $object->Event ) {
        case "subscribe":
            $contentStr = "欢迎您关注xxx";
        case "unsubscribe":
            break;
        case "CLICK":
            switch ( $object->EventKey ) {
            case "V1001_GETCODE":
                $contentStr = "xxx";
                break;
            case "V1002_HISTORY":
                $contentStr[] = array( "Title" =>"最后一条历史记录",
                    "Description" =>"xxx",
                    "PicUrl" =>"xxx",
                    "Url" =>"xxx" );
                break;
            case "V2001_INTERDUCE":
                $contentStr[] = array( "Title" =>"xxx",
                    "Description" =>"xxx",
                    "Url" =>"http://mp.weixin.qq.com/xxx" );
                break;
            case "V3001_JOIN":
                $getuid = $this->getUid( $object );
                if ( $getuid==1 ) {
                    $contentStr = 'Could not connect: '.mysql_error();
                }else {
                    $contentStr = "唯一码：".$getuid;
                }
                break;
            default:
                $contentStr[] = array( "Title" =>"默认菜单回复",
                    "Description" =>"xxx",
                    "PicUrl" =>"xxx",
                    "Url" =>"xxx" );
                break;
            }
            break;
        default:
            break;

        }
        if ( is_array( $contentStr ) ) {
            $resultStr = $this->transmitNews( $object, $contentStr );
        }else {
            $resultStr = $this->transmitText( $object, $contentStr );
        }
        return $resultStr;
    }

    private function transmitText( $object, $content, $funcFlag = 0 ) {
        $textTpl = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[text]]></MsgType>
                    <Content><![CDATA[%s]]></Content>
                    <FuncFlag>%d</FuncFlag>
                    </xml>";
        $resultStr = sprintf( $textTpl, $object->FromUserName, $object->ToUserName, time(), $content, $funcFlag );
        return $resultStr;
    }

    private function transmitNews( $object, $arr_item, $funcFlag = 0 ) {

        if ( !is_array( $arr_item ) )
            return;

        $itemTpl = "<item>
                    <Title><![CDATA[%s]]></Title>
                    <Description><![CDATA[%s]]></Description>
                    <PicUrl><![CDATA[%s]]></PicUrl>
                    <Url><![CDATA[%s]]></Url>
                    </item>";
        $item_str = "";
        foreach ( $arr_item as $item )
            $item_str .= sprintf( $itemTpl, $item['Title'], $item['Description'], $item['PicUrl'], $item['Url'] );

        $newsTpl = "<xml>
                    <ToUserName><![CDATA[%s]]></ToUserName>
                    <FromUserName><![CDATA[%s]]></FromUserName>
                    <CreateTime>%s</CreateTime>
                    <MsgType><![CDATA[news]]></MsgType>
                    <Content><![CDATA[]]></Content>
                    <ArticleCount>%s</ArticleCount>
                    <Articles>$item_str</Articles>
                    <FuncFlag>%s</FuncFlag>
                    </xml>";
        $resultStr = sprintf( $newsTpl, $object->FromUserName, $object->ToUserName, time(), count( $arr_item ), $funcFlag );
        return $resultStr;
    }

    /* 生成唯一码*/
    public function getUid( $object ) {
        $getOpenid = $object->FromUserName;
        $con = mysql_connect( "localhost", "root", "xxx" );
        mysql_select_db( "xxx", $con );
        if ( !$con ) {
            return 1;
        }
        $flag = true;
        $getUserresult = mysql_query( "SELECT * FROM loginuser WHERE openid = '".$getOpenid."'" );
        $getuserrow = mysql_num_rows( $getUserresult );
        if ( $getuserrow>0 ) {
            $userrow = mysql_fetch_array( $getUserresult );
            if ( $userrow['state']==0 ) {
                return $userrow['userPassword']."[未完成考试]";
                $flag = false;
            }else {
                return $userrow['userPassword']."[已完成考试]";
                $flag = false;
            }
        }
        /* 循环确定唯一性 */
        while ( $flag ) {
            $uid = uniqid( true );
            $uid = substr( $uid, -8 );
            $result = mysql_query( "SELECT * FROM loginuser where userPassword = '".$uid."'" );
            $row = mysql_num_rows( $result );
            if ( $row == 0 ) {
                mysql_query( "INSERT INTO loginuser (userPassword,state,openid) VALUES ('".$uid."','0','".$getOpenid."')" );
                mysql_close( $con );
                return $uid;
                $flag =false;

            }
        }

    }
    private function getUidtest( $object ) {
        return $object->FromUserName;
    }
    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;
        }
    }
}

?>

微信开发模式（php）