JavaScript Insert TextBox Dynamically

function AddRowDynamicallytoTable()
{
var newRow = document.all.Table1.insertRow();// Table1 = Table Id
oCell = newRow.insertCell();
oCell.width = "150px";
oCell.align = "right";
oCell.valign = "middle";
oCell.Class = "CssClass";
oCell.innerHTML = "<input name='text' type='text' onKeyPress='JavaScript:return fnNumeric();' id='txt"+(iMaxCount.length+1)+"' value='id=txt"+(iMaxCount.length+1)+"' class='txtbox' style='text-align:right' size='8' maxlength='3' align='left' width='15'/>";
}

function fnNumeric()
{
if (event.keyCode < 48 || event.keyCode > 57 ) event.returnValue = false;
}