一段代码，求读懂。然后求助加上一段

if($type == "text")
{
if(mb_strlen($keyword,'utf8')<11){
$contentStr = "请输入不少于11个字符的信息！";
$resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
echo $resultStr;
}else
{
$resultStr="";
ref_key();
if(send($keyword."$tail")=="1")
$contentStr = "您已经成功匿名发送信息！";
else
$contentStr = "发送失败，请稍等一会再尝试重新发送！";
$resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
echo $resultStr;
}
}else if($type == "event")