Questions about the administrator of the library management system verification

Concerning the question of the administrator of the library management system verification, the younger brother beginner PHP has a set of source code about the library management system in the research book. I installed the wamp5 integrated environment. I put the database under the DATA folder of MYSQL. after other configurations are completed, login is entered. when the account and password on the php interface are correct, the system keeps prompting that the account is incorrect. sorry, please help me paste the checklog code: & lt ;? Phps questions about the administrator of the library management system verification
I installed the wamp5 integrated environment for the source code of the library management system on the research book of PHP. I put the database under the MYSQL DATA folder, and other configurations are completed. that is, login. when the account and password on the php interface are correct, the system keeps prompting that the account is incorrect. sorry, please help me paste the checklog code:

Session_start ();
$ A_name = $ _ POST [name]; // user name for receiving form submissions
$ A_pwd = $ _ POST [pwd]; // The password for receiving form submissions

Class chkinput {// define a class
Var $ name;
Var $ pwd;

Function chkinput ($ x, $ y ){
$ This-> name = $ x;
$ This-> pwd = $ y;
}

Function checkinput (){
Include ("conn/conn. php"); // connect to the data source
$ SQL = mysql_query ("select * from tb_manager where name = '". $ this-> name. "'& pwd = '". $ this-> pwd. "'");
$ Info = mysql_fetch_array ($ SQL); // Retrieve the administrator name and password
If ($ info = false) {// if the administrator name or password is incorrect, a prompt is displayed.
Echo"