小提示：
Do not use getimagesize() to check that a given file is a valid image. Use a purpose-built solution such as the Fileinfo extension instead.
——php官方手册并不建议使用此方法来检测是否为图片文件。
Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in G:\caishichang\lib\mysql.func.php on line 7
mysql_fetch_array() expects parameter 1 to be resource, boolean given in的错误提示，是因为在mysql.func.php中的mysqli_fetch_array($result,$type)中的result需要资源值，而如果账号密码不存在会导致没有值报错。因为在这一句之前加上一个判断，如果sql查不到值，则直接返回false就可以了。
