Pagination Using Javascript

function Pagination(d){
 this.data = d;
 this.item = 10;
 this.numPage = Math.ceil(this.data.length/this.item);
}

Pagination.prototype.setFirstPage = function(){
 var arr = new Array();
 for(i=0;i<this.item;i++){
  arr[i] = this.data[i];
 }
 return arr;
}

Pagination.prototype.setLastPage = function(){
 var arr = new Array();
 var startLastIndex = (this.numPage-1) * this.item;
 for(i=0;i<(this.data.length-startLastIndex);i++){
  arr[i] = this.data[startLastIndex];
  startLastIndex++;
 }
 return arr;
}

Pagination.prototype.next = function(){
 
}

Pagination.prototype.previous = function(){

}

Pagination.prototype.displayAtPage = function(n){
var arr = new Array();
 n = n-1;
 var startIndex = n * this.item;
 for(i=0;i<(this.item);i++){
  arr[i] = this.data[startIndex];
  startIndex++;
 }
 return arr;
}