Código PHP :
<? $dbhost='localhost'; $dbusername='xxx'; $dbuserpass='xxx'; $dbname='xxxx'; conectando mysql_connect ($dbhost, $dbusername, $dbuserpass); mysql_select_db($dbname) or die("Cannot select database"); if (isset($_POST["username"])) { $username = $_POST["username"]; $password = $_POST["password"]; $cpassword = $_POST["cpassword"]; $email = $_POST["email"]; if($username==NULL|$password==NULL|$cpassword==NULL|$email==NULL) { echo "un campo está vacio."; }else{ if($password!=$cpassword) { echo "Las contraseñas no coinciden"; }else{ $checkuser = mysql_query("SELECT username FROM users WHERE username='$username'"); $username_exist = mysql_num_rows($checkuser); $checkemail = mysql_query("SELECT email FROM users WHERE email='$email'"); $email_exist = mysql_num_rows($checkemail); if ($email_exist>0|$username_exist>0) { echo "EL nombre de usuario o la cuenta de correo estan ya en uso"; }else{ $query = "INSERT INTO users (username, password, email) VALUES('$username','$password','$email')"; mysql_query($query) or die(mysql_error()); echo "El usuario $username ha sido registrado de manera satisfactoria."; echo "<script>document.location.href='usuario.php';</script>\n"; } } } } ?>
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