table column calculate

by lemon kazi

HTML

<table>
    <tr>
        <td width="40px">1</td>
        <td>Number</td>
        <td><input class="txt" type="text" name="txt" /></td>
    </tr>
    <tr>
        <td>2</td>
        <td>Number</td>
        <td><input class="txt" type="text" name="txt" /></td>
    </tr>
    <tr>
        <td>3</td>
        <td>Number</td>
        <td><input class="txt" type="text" name="txt" /></td>
    </tr>
    <tr id="summation">
        <td  colspan ="2" align="right">
            Sum :
        </td>
        <td>
          <input type="text" id='sum1' name="input" />
        </td>
        </span>
        </td>
    </tr>
</table>

JavaScript

$(document).ready(function() {
    //this calculates values automatically 
    calculateSum();

    $(".txt").on("keydown keyup", function() {
        calculateSum();
    });
});

function calculateSum() {
    var sum = 0;
    //iterate through each textboxes and add the values
    $(".txt").each(function() {
        //add only if the value is number
        if (!isNaN(this.value) && this.value.length != 0) {
            sum += parseFloat(this.value);
            $(this).css("background-color", "#FEFFB0");
        }
        else if (this.value.length != 0){
            $(this).css("background-color", "red");
        }
    });
 
	$("input#sum1").val(sum.toFixed(2));
}