php怎么向mysql数据库中插入变量?

admindid为int型 其他变量均为varchar型 怎么调试都不成功 网上各种答案都试过以下是错误提示Warning: mysql_query() expects parameter 1 to be string, object given in D:\phpStudy\WWW\addAction.php on line 17Warning: mysql_free_result() expects parameter 1 to be resource, null given in D:\phpStudy\WWW\addAction.php on line 22Warning: mysql_close() expects parameter 1 to be resource, object given in D:\phpStudy\WWW\addAction.php on line 23我也分不清哪里错了 麻烦大神指教 在我想的是把values('$adminid','$adminname','$password','$rolename')";这里的单引号换成双引号,可是又会出现下面错误Parse error: syntax error, unexpected '$adminname' (T_VARIABLE) in D:\phpStudy\WWW\addAction.php on line 16

变量那里加上花括号({})即可。
$add = "insert into admin(adminid,adminname,password,rolename) values('{$adminid}','{$adminname}','{$password}','{$rolename}')";
把第一行与第二行改为:
$conn = mysqli_connect('localhost','root','root','news');
mysqli_connect的第四个参数就是库名。
温馨提示:答案为网友推荐,仅供参考