JSFiddle - React, Tailwind, and code Playground

by Harisankaran Parameswaran

HTML

<h1>Sub-total Calculation</h1>

	<form onsubmit='return false;'>
		<input type="text" id="fld" placeholder="Enter in subtotal"/>
		<button type="submit" onclick="return calcSub();">Calculate</button><br> 
		<span id="sub-total"></span><br> 
		<span id="tax"></span><br> 
		<span id="total"></span><br> 
	</form>

JavaScript

function calcSub(){

			var input = document.getElementById('fld'),
				subTotal = document.getElementById('sub-total'),
				tax = document.getElementById('tax'),
				total = document.getElementById('total');

			var subTotalCalc = input.value / 1.06;

			var flag = true;


			if(input.value == "" || input.value == null){
				alert("Please enter in a total!");
				return false;
			} else {
				subTotal.innerHTML = "Subtotal:" + " " + "$" + subTotalCalc;
				tax.innerHTML = "Tax:" + " " + "$" + input.value - subTotalCalc;
				total.innerHTML = input.value;
				return flag;
			}

		}