Questions about the Library Management System verification Administrator

Questions about the Library Management System validation Administrator
Little Brother Learning PHP in the research book a set of books on the management system of the source code I installed the WAMP5 integration environment I put the database into the MySQL Data folder and other configuration completed in the time of entry is the Login.php interface account password is correct, always prompt the account error The great God helps me to put out the Checklog code:

Session_Start ();
$A _name=$_post[name]; User name to receive form submission
$A _pwd=$_post[pwd]; Receive password for form submission

Class chkinput{//Defining classes
var $name;
var $pwd;

function Chkinput ($x, $y) {
$this->name= $x;
$this->pwd= $y;
}

function Checkinput () {
Include ("conn/conn.php"); Connecting to a data source
$sql =mysql_query ("select * from Tb_manager where name= '". $this->name. "' & pwd= '". $this->pwd. "'");
$info =mysql_fetch_array ($sql); Retrieving the administrator name and password is correct
if ($info ==false) {//If the administrator name or password is incorrect, the relevant message pops up
echo "";
Exit
}
else{//If the administrator name or password is correct, the relevant message pops up
echo "";
$_session[admin_name]= $info [name];
$_session[pwd]= $info [pwd];
}
}
}
$obj =new chkinput (Trim ($name), Trim ($pwd)); Creating objects
$obj->checkinput (); Call class
?>


------Solution--------------------
$obj =new chkinput (Trim ($name), Trim ($pwd)); Creating objects
There is no value in the $name, $pwd

$A _name=$_post[name]; User name to receive form submission
$A _pwd=$_post[pwd]; Receive password for form submission
You only $A _name, $A _pwd.

------Solution--------------------
You haven't seen it yet.
$obj =new chkinput (Trim ($name), Trim ($pwd));
$A _name

What to do? Change to the same.

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