Home php教程 php手册 PHP错误Warning:mysql_query()的解决方法

PHP错误Warning:mysql_query()的解决方法

Jun 13, 2016 am 11:36 AM
mysql php query warning hint method of solve mistake

php提示错误:Warning: mysql_query() [function.mysql-query]: Access denied for user 'ODBC'@'localhost' (using password: NO)

代码:

Copy to Clipboard引用的内容:[www.bkjia.com] class mysqlClass
{
function mysqlClass($host='localhost',$user='root',$pw='',$db='mysql')
{
$this->link=mysql_connect($host,$user,$pw);
mysql_select_db($db);
}
function query($sql){
mysql_query($sql);
}
function __destruct(){
mysql_close($this->link); //multi construct will cause error
}
// liehuo,net
}
$db=new mysqlClass();
$db=new mysqlClass();
$db->query("select * from user");

原因:

mysqlClass第二次初使化时,先初使化mysqlClass,得到跟第一个$db相同的$this->link,然后调用__construct函数会把this->link关闭。

最后导致$db中mysql资源为空。弹出错误

解决办法:

$db=$db?$db:new mysqlClass(); 

或者

$this->link=mysql_connect($host,$user,$pw,true);

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