Question: I have following html file:

```
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Fancy Website</title>
</head>
<body>
    <div id="content_login">
        <form method="post" action="app.php">
            <table>
                <thead>Please Login for more fancy Content!</thead>
                <tr>
                    <td>Username</td>
                </tr>
                <tr>
                    <td><input type="text" name="username"></td>
                </tr>
                <tr>
                    <td><input type="submit" name="login" value="Login"></td>
                </tr>
            </table>
        </form>
    </div>
</body>
</html>

```

And this is my php script:

```
<?php
    if(isset($_POST['login'])) {
        echo "Hello " . $_GET["username"];
    }
?>

```

Yeah simply nothing, but I only wanted to test, if a script would work when the Login Button is pressed. Surprise: It's not. I open index.html in my browser and the html part works properly, but if I press the Login Button the browser shows me this:

```
<?php
    if(isset($_POST['login'])) {
        echo "Hello " . $_GET["username"];
    }
?>

```

I guess it's a syntax issue but I can't find it. Maybe you see it.
Thanks a lot!

Answer: 
My advice would be to use:

```
<?php
    if (isset($_POST['login']))
    {
        $username = $_POST['username'];

        if (!empty($username))
        {
            echo "hello $username";
        } else {
            echo "You must fill in the username!";
        }
    }
?>

```

To be honest, I would change index.html to index.php and place it into the top of that page so all errors etc are passed through one file.
First I think you don't have apache server running to make your PHP code works correctly.
And you are sending the data using POST no GET, you must use the POST method to handle the data.

```
<?php
    if(isset($_POST['login'])) {
        echo "Hello " . $_POST["username"];
    }
?>

```