PhantomJS click a link on a page

I have written some parts of a PhantomJS application. I am parsing on a website where I am writing username and password to a formular. After this I have to click on a link. Whereas I get this error:

TypeError: 'undefined' is not a function (evaluating 'myLink.click()')

  phantomjs://webpage.evaluate():11
  phantomjs://webpage.evaluate():22
  phantomjs://webpage.evaluate():22

This is my PhantomJS code:

if(document.getElementById("m_Content_submitbtn2").getAttribute('data-role') == "button"){
        var myLink = document.getElementById("m_Content_submitbtn2");   
    myLink.click();
}

And this is my link:

<div class='button'><a href="#" data-role="button" tabindex='0' onclick='WebForm_DoPostBackWithOptions(new WebForm_PostBackOptions(&quot;m$Content$submitbtn2&quot;, &quot;&quot;, true, &quot;&quot;, &quot;&quot;, false, true)); return false;' id="m_Content_submitbtn2">Log ind</a></div>&nbsp;