Boostrap multiselct dropdown to have multiple selected values in prior

I have an issue to get the multiselect dropdown selected based on the data. This is update action. When I go to update the roles I need this multislect to have previously checked box to be checked once I enter the page. I am doing in the below method as code pasted.

jquery Code

$(".checkbox-val").hide();
    var count = 1;
    if(count == 1){
    $(".checkbox-val").hide();
        var a = "["+$(".checkbox-val").text()+"]";
        var arr = a.split(",");

        console.log(a);

        $("#lstFruit").val(a); 
        alert(a);
         $("#lstFruit").multiselect({
            includeSelectAllOption: false,
            numberDisplayed: 0,
            enableFiltering: true,
        });
         $("#lstFruit").multiselect("refresh");

    }

and my div code from where I am retrieving the text

  for ($i=0; $i < $count; $i++){ ?>
              <div class="checkbox-val" style="font-size: 0px;"><?php echo  '"'.$user1[$i].'"'.',';?> </div>
         <?php } ?>

• When I alert or log "var a" I get this output ["Risk Assessor", "Risk Manager",].

• When I put the same content in

  $("#lstFruit").val(["Risk Assessor", "Risk Manager",]);

• With above code I get selected checkbox as expected.

• Instead of the above code I use variable a in place of the array above.

  $("#lstFruit").val(a);

What can I do to achieve what I want. Is there any alternative for this?