//clear rows for table
function clearAllRows(oTable){
for(var i = oTable.rows.length - 1; i > 0; i--){
oTable.deleteRow(i);
}
}
function addRows(oTable, Person){
var rowid = oTable.rows.length;
var row = oTable.insertRow(rowid);
var cell=row.insertCell();
cell.innerText = Person.getId();
var cell = row.insertCell();
cell.innerHTML = Person.getName();
var cell=row.insertCell();
cell.innerHTML=Person.getAge();
}
function sortBy(index){
var oTable = document.getElementById("t1");
//get data from table
var arr = new Array();
//skip the first row, because it is the head of the table
for(var i = 1; i < oTable.rows.length; i++){
var id = oTable.rows[i].cells[0].innerText;
var name = oTable.rows[i].cells[1].innerText;
var age = oTable.rows[i].cells[2].innerText;