Looks like you're trying to convert totalamount to a string when totalamount is null. You need to only get the string if it contains a value.
Try this:
var th = ['', 'Thousand', 'Million', 'Billion', 'Trillion'];
var dg = ['Zero', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine'];
var tn = ['Ten', 'Eleven', 'Twelve', 'Thirteen', 'Fourteen', 'Fifteen', 'Sixteen', 'Seventeen', 'Eighteen', 'Nineteen'];
var tw = ['Twenty', 'Thirty', 'Forty', 'Fifty', 'Sixty', 'Seventy', 'Eighty', 'Ninety'];
function toWords(s) {
s = s.toString();
if (s != parseFloat(s))
return 'not a number';
var x = s.indexOf('.');
if (x == -1) x = s.length;
if (x > 15)
return 'too big';
var n = s.split('');
var str = '';
var sk = 0;
for (var i = 0; i < x; i++) {
if ((x - i) % 3 == 2) {
if (n[i] == '1') {
str += tn[Number(n[i + 1])] + ' '; i++; sk = 1;
}
else if (n[i] != 0) {
str += tw[n[i] - 2] + ' '; sk = 1;
}
}
else if (n[i] != 0) {
str += dg[n[i]] + ' ';
if ((x - i) % 3 == 0) str += 'Hundred '; sk = 1;
}
if ((x - i) % 3 == 1) {
if (sk) str += th[(x - i - 1) / 3] + ' '; sk = 0;
}
}
if (x != s.length) {
var y = s.length; str += 'point ';
for (var i = x + 1; i < y; i++) str += dg[n[i]] + ' ';
}
return str.replace(/\s+/g, ' ');
}
function NumberToWord(executionContext) {
setInterval(function(){
var varInteger = null;
var num = Xrm.Page.getAttribute("totalamount").getValue();
//console.log(num);
if(num != null)
{
num = num.toString();
num = num.replace(/[\, ]/g, '');
num = num.replace(/[\$ ]/g, '');
var splitNum = num.split(".");
if(splitNum[0] == null || splitNum[0] == "0")
{
varInteger = "Zero";
}
else
{
varInteger = toWords(splitNum[0]);
}
if(splitNum[1] == null)
{
varFraction = "Zero";
}
else
{
varFraction = toWords(splitNum[1]);
}
//console.log(varInteger + " - " + varFraction);
Xrm.Page.getAttribute("wa_totalamountinwords").setValue(varInteger);
Xrm.Page.data.save();
}
}, 2000);
}
