How to deselect the more selected options from combobox?

[Rajesh Gite]

I have a combobox, in that i have taken list of districts so i have provide a facility to select max 5 districts. If user by mistake select more than that i have to give an alert and when user click on ok of the alert msg the the more select option have to deselect. How to do that i am tring on code. see below

function validateListBox()
{
//debugger;
selectedArray=[];
  var selObj = document.getElementById('type1');
  var i;
  var count = 0;
  var no = 0;
  for (i=0; i<selObj.options.length; i++) {
    if (selObj.options[i].selected)
    {
      statelist = selObj.options[i].text;
      count++;
      selectedArray.push(statelist);
 
      }
      if(count > 4)
      {
        //debugger;
        alert("Select four "+type+" at a time only.");
 
        if(i==selObj.options.length-1)
        {
            for (i=selObj.options.length-1; i>0; i--) 
            {
                if (selObj.options[i].selected)
                {    
                    no++;
                    if(no>4)
                    {
                        selObj.options[i].selected=false;
                        return false;
                    }
                }
            }
        }
        else
        {
        selObj.options[i].selected=false;
        return false;
        }
      }

[Dormilich]

it doesn’t look wrong at first glance. what part of your code is not working?