Fragment identifier in form action attribute
===

I have a form which I'd like to post to the same page. The form action contains a fragment identifier for the element on the page that contains it - what I want it to do is post the data, then reload the same page at the same point so the user doesn't need to scroll down.

example index.php:

    <div>
      some very long content that pushes my form down the page
    </div>
    <div id="myDiv">
      <form action="index.php#myDiv" method="post">
        <input name="abc" value="123"/>
        <input type="submit" value="submit"/>
      </form>
    </div>

However I have a couple of problems - firstly I'm not sure if this is good practice and can't find much on what *is* considered good practice with fragment identifiers. 

Second, some others have said that sometimes the form "jumps to the top" when they click submit. I haven't been able to reproduce this yet but it seems pretty obvious that instead of posting the data, the browser is going with the fragment identifier action instead.

Can anyone suggest a better way to do this?