function changeToForeign() {
    var val = document.getElementById("ChangeToUSD").value;
    var txtInput = document.getElementById("txtForeign").value;
    document.getElementById("txtChange").innerHTML = formatNumber_input_decimal_format_en(val * txtInput, 2);
}

function changeToVND() {
    var val2 = document.getElementById("ChangeToVND").value;
    var txtInput2 = document.getElementById("txtVND").value;
    document.getElementById("divValueMoney").innerHTML = formatNumber_input_decimal_format_en(txtInput2 / val2, 2);
}