使用php和mySql进行用户身份验证

Question

Am facing challenges in the following code; please help:

<?php
    session_start();
    $con = mysql_connect("localhost","root","");
    if (!$con){
       die('Could not connect: ' . mysql_error());
    }

    $db_exist = mysql_select_db("seta", $con);

    $myUName = $_POST["username"];
    $myPwd = $_POST["pwd"];
    $loFmUname = strtolower($myUName);

    if($db_exist){
        $sql = "SELECT * FROM Persons WHERE $loFmUname = 'strtolower($db_field['UserName'])' AND $myPwd = '$db_field['UserPwd']'";
        $result = mysql_query($sql);

        if($result){
            $_session['loged'] = '$loFmUname';
            header('location:index.html');
            die();
        }

        else{
            echo"Invalid username and/or password please";
            echo "<a href='login.php'>try again</a>";
        }

    }

    else{
        echo "Sorry Database Not Found";
    }


 mysql_close($con);
 ?>

The error is coming on line 15.

Note that strtolower() is being used to ignore case-sensitive username.

Answer 1

Change the line

$sql = "SELECT * FROM Persons WHERE $loFmUname = 'strtolower($db_field['UserName'])' AND $myPwd = '$db_field['UserPwd']'";

By this one

$sql = "SELECT * FROM Persons WHERE $loFmUname = '".strtolower($db_field['UserName'])."' AND $myPwd = '".$db_field['UserPwd']."'";

This may help you.

Thanks