Javascript String removeSubstring(char,occurance)

String.prototype.removeSubstring = function(char,occurance) 
{


 var temp='';
 if(occurance==undefined)
 {
  for (var i = 0; i < this.length; i++) 
  {//from   w w w.  j  a  v  a  2  s. c  om
   if(char!==this[i])
   {
    temp+=this[i];
   }
  } 
 
 }
 else
 {
  var flag = true;
  var ct=parseInt("0");

  for (var i = 0; i < this.length ; i++) 
  {
   if(char===this[i])
   {
    ct++;
    flag=(ct===parseInt(occurance))?false:true;
   }
   else
   {
    temp+=this[i];
   }

   if(!flag)
   {
    temp+=this.substr(i+1,this.length);
    return temp;
   }
  }

 }

 return temp;
};

var str1 = 'aaa';
console.log(str1.removeSubstring('a', 2)); 

var str2 = 'aaabbbb'; 
console.log(str2.removeSubstring('a'));