I managed to create a condition to detect anchor link, but after that how do I store the anchor link in my anchor_num variable, so that I can redirect the use to specific url?

<script type="text/javascript">

$(function(){

    if(window.location.hash){

        var anchor_num = "anchorString";
        window.location = "#"+ anchor_num;

    } else
          {
            //redirect to default page
          }
});

</script>

By appending or changing hash the browser wouldn't refresh your page. You should call window.location.reload() after you've set the hash:

window.location = "#"+ anchor_num;
window.location.reload()

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