Display Full name instead of username in php - php

Question

I have a login table containing Name, Username and Password. When user logins with username and password, I want to display the name of the user instead of the username. I want to display user's name in the next page as Welcome NAME instead of Welcome USERNAME.
Here is the HTML:
<form class="form-basic" method="post" action="login.php">
<div class="form-row">
<label>
<span>Username</span>
<input type="text" name="username" id="username" >
</label>
</div>
<div class="form-row">
<label>
<span>Password</span>
<input type="password" name="password" id="password" >
</label>
</div>
<div class="form-row">
<button type="submit" name="submit" id="submit"/>SUBMIT</button>
</div>
</form>
PHP code:
<?php
// your values are stored in cookies, then you can login without validate
include_once 'db.php';
// login validation in php
if (isset($_POST['submit'])) {
$name = $_POST['name'];
$username = mysql_real_escape_string(stripslashes($_POST['username']));
$password = $_POST['password'];
$query = mysql_query("select name,username,password from reglogin where username='".$username."' AND password='".$password."'");
$numrows = mysql_num_rows($query);
if ($numrows != 0) {
while ($row=mysql_fetch_assoc($query)) {
$dbname=$row['username'];
$dbpassword=$row['password'];
}
if($username == $dbname && $password == $dbpassword)
{
$_SESSION['sess_user']=$name;
echo "<script>window.open('registration1.php','_self')</script>";
}
}
else {
echo "<script>alert('Invalid! Username or Password')</script>";
}
}
?>

Answer 1

you have input
<input type="text" name="username" id="username" >
In php side you are accessing
$name=$_POST['name'];
you have to change above line to
$name=$_POST['username'];
or you have to update
$_SESSION['sess_user']=$name;
to
$_SESSION['sess_user']=$row['username'];
Updated
As you need name so you can set name to session
$_SESSION['sess_user']=$row['name'];

Answer 2

You can replace your code with this one:
Your errors:
In the line number 8 you have an Undefined Index called name.
You are using that in value for $_SESSION which you can get from
database while fetching the username and password.
Review your query what you are selecting and what you fetched.
Changes I have made:
check line number 8.
check line number 20
Hope this will help you.
// your values are stored in cookies, then you can login without validate
include_once 'db.php';
// login validation in php
if (isset($_POST['submit'])) {
// $name = $_POST['name']; // this is not posted
$username = mysql_real_escape_string(stripslashes($_POST['username']));
$password = $_POST['password'];
$query = mysql_query("select name,username,password from reglogin where username='".$username."' AND password='".$password."'");
$numrows = mysql_num_rows($query);
if ($numrows != 0) {
while ($row=mysql_fetch_assoc($query)) {
$dbname=$row['username'];
$dbpassword=$row['password'];
$name =$row['name'];
}
if($username == $dbname && $password == $dbpassword)
{
$_SESSION['sess_user']=$name;
echo "<script>window.open('registration1.php','_self')</script>";
}
}
else {
echo "<script>alert('Invalid! Username or Password')</script>";
}
}
?>