How to make Subtract textbox value be smaller/equal to Price textbox value and show the Price in another textbox in Asp.net core C#?

Question

Tools used Visual Studio 2019, Asp.net core 5.0 (.net 5.0)
I have 3 textboxes: Pricex, Subtractx and Sumx.
What i want is if the Subtractx value gets bigger or equal to Price value, then Subtract = Price and Sum = Price.
If it is possible, can this be done directly in C#?

Im trying this JS code but its not working

    <script>
    $(function () {
        getSum();
    })
    $("#Subtractx").keyup(function () {
        getSum();
    })
    function getSum() {
        if ($("#Subtractx").val() >= $("#Pricex").val())
        {
            $("#Subtractx").val($("#Pricex").val());
            var sum = /*parseInt($("#Rows_Qty").val()) * */parseInt($("#Pricex").val()) - parseInt($("#Subtractx").val())
            $("#SumX").val(sum);
        }
        var sum = /*parseInt($("#Rows_Qty").val()) * */parseInt($("#Pricex").val()) - parseInt($("#Subtractx").val())
        $("#SumX").val(sum);
    }
</script>

Answer 1

Below is a working demo, you can check it.

<label>Price</label>
<input type="number" id="Pricex"/>
<label>Subtract</label>
<input type="number" id="Subtractx"/>
<label>Sum</label>
<input type="number" id="SumX"/>
@section Scripts
{ 
    <script>
        $(function () {
            getSum();
        })
        $("#Subtractx").keyup(function () {
            getSum();
        })
        function getSum() {
            var x = parseFloat($("#Subtractx").val());
            var y = parseFloat($("#Pricex").val());
            if (x >= y) {
                $("#Subtractx").val($("#Pricex").val());
                var z = parseFloat($("#Subtractx").val());
                var sum = (y - z).toFixed(2);
                $("#SumX").val(sum);
            }
            else {
                var sum = (y - x).toFixed(2)
                $("#SumX").val(sum);
            }
          
        }
    </script>
}

Test result: