今天在开发微信自定义菜单的时候碰到问题了，后买你解决了，就分享给大家．构造了一个如下的数组通过curl发送post json数据过去了．结果得到里一个字符集错误的错误提示，后面使用urlencode，及配合urldecode进行了解决．

顺便把贴出来部分代码，有需要直接拿走即可．

function httpCurlPost($url,$json)
{ //发送json post
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
    curl_setopt($ch, CURLOPT_POSTFIELDS, $json);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array(
            'Content-Type: application/json',
            'Content-Length: ' . strlen($json))
    );
    $result = curl_exec($ch);
    return($result);
}
//设置自定义菜单
function setUserMenu()
{
    $url = 'https://api.weixin.qq.com/cgi-bin/menu/create?access_token='.$this->getWXAT();

    $arr = array(
                        'button'=>array(
                            array(
                                'type'=>'click',
                                'name'=>'hello',
                                'key'=>'item1',
                            ),
                            array(
                                'name'=>urlencode('午饭'),
                                'sub_button'=>array(
                                    array(
                                        "name"=>urlencode("歌曲"),
                                        "type"=> "click",
                                        "key"=>"songs",
                                    ),
                                    array(
                                        "name"=>urlencode('大片'),
                                        "type"=>'view',
                                        "url"=>'http://iphp.cc'
                                    ),// the second two level menu

                                ),
                                'key'=>'item2',
                            ),
                            array(
                                    'name'=>urlencode('吃晚饭'),
                                    'type'=>'view',
                                    'url'=>'http://www.koalapass.cn',
                                ),

            ),
        );
    $json = urldecode(json_encode($arr));
    $res = json_decode($this->httpCurlPost($url,$json),TRUE);
    var_dump($res);
｝    

//获取wechat token
function getWXAT()
{
    if($_SESSION['access_token']&&($_SESSION['expire_time']>time())){
        return $_SESSION['access_token'];
    }else{
        $APPID = '你的wei信appid';
        $secret = '你的密钥';
        $url = 'https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid='.$APPID.'&secret='.$secret;
        $arr = json_decode($this->httpCurl($url),TRUE);
        $_SESSION['access_token'] = $arr['access_token'];
        $_SESSION['expire_time'] =  time()+7000;
        return $arr['access_token'];
    }
}