PHP if(isset($_POST['form-name'] [duplicate]

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I'm having this issue where I can't get into my if-statement. And I went code blind on all this - at this moment, so can any of you guys out there help me understand what's going on? I have tried to use if(isset($_POST["form-name"])) { code block } else { echo 'Error, not inside if-statement'; } And I have tried to use !empty instead of the isset..

if (!empty($_POST["login-form"])) {
$username = $_POST['username'];
$password = $_POST['password'];
if (DB::query('SELECT username FROM users WHERE username=:username', array(':username'=>$username)))  

I want it to get into this first if-statement.