是否可以使用下拉菜单影响返回的值

I'm trying to set up an html form that allows the user to select a field from a drop-down menu, then specify the information for that field. For example, if they select "Name" from the menu, then enter a name, it posts a specific response.

Here's how the html looks:

    <form action="hello.php" method="post">
    <select>
    <option disabled="yes" selected="yes">Select...</option>
    <option value="name">Name</option>
    <option value="gender">Gender</option>
    <option value="birthday>Birthday</option>
    <input name="name" type="text" />
    <input type="submit" value="Submit">
    </form>

What I'm trying to do is have the php code change responses based on what's submitted. Here's the php code:

   $name = $_POST['name'];
   $gender = $_POST['gender'];
   $bday = $_POST['birthday'];

With the responses:

    echo "Hello, $name!";
    echo "Your gender is $gender!";
    echo "Happy birthday on $birthday!";

depending on what option they select. (I haven't finished the if/elseif/else statements yet because I'm not sure if they're influenced by how the information is recieved.)

Is it possible to do this? I know that my code will only ever return $name in this example, because

   <input name="name"...>

But I don't know if it's possible to have the text field's information identified by the drop-down menu. I imagine it's probably possible with Javascript, but I've never used Javascript and wouldn't know how to do this. Thanks!

EDIT: I found an answer. I ended up setting

   <input type="text" name="submit" />

in my html code, and

   $submit = $_POST['submit'];

in my php code. Now if I do something such as

   echo $submit;

it returns whatever I entered in the html page. Thanks again!

<form action="hello.php" method="post">
<select name="myselectbox">
<option disabled="yes" selected="yes">Select...</option>
<option value="name">Name</option>
<option value="gender">Gender</option>
<option value="birthday>Birthday</option>
<input name="name" type="text" />
<input type="submit" value="Submit" />
</form>

Then in hello.php do this at the top of the file.

 var_dump($_POST);

that should help you understand the relationship between a html form and the PHP Postback Form Handler (in your case hello.php)