Why am I getting an NaN value?
Question
My jQuery is:
$("#listDB").on("change", ".qfStyle", function(event) {
var id = $(this).parents("tr").find('.itemCbox').val();
$qnty = $("#qnty"+id);
$unit = $("#unit"+id);
$price = $("#price"+id);
if($(this).parents("tr").find('.pbo').text()=="Kilos")
{
if(this.value<1)
{
$qnty.text(this.value*1000);
$unit.text("gm");
var data = "action=getPrice&id="+id;
$.post("addBill.php", data, function(json) {
alert(json.price);
$price.text(json.price*this.value);
}, 'json');
}
}
});
The JSON data returned by the server is:
{"price":"52.00"}
Here, this refers to a textbox. I'm getting the value NaN for the expression:
$price.text(json.price*this.value);
But I've ensured that both this.value and json.price are both numbers. So, why do I get NaN when I multiply them?
2 answers
solution1
8 ACCPTED 2016-12-29 06:40:10
The problem is that this isn't in a scope of a post function.
Check the code below. I added a new variable value which holds the value of this.value and which should be available even in a post function.
$("#listDB").on("change", ".qfStyle", function(event) {
var id = $(this).parents("tr").find('.itemCbox').val();
$qnty = $("#qnty"+id);
$unit = $("#unit"+id);
$price = $("#price"+id);
var value = this.value;
if($(this).parents("tr").find('.pbo').text()=="Kilos")
{
if(value<1)
{
$qnty.text(value*1000);
$unit.text("gm");
var data = "action=getPrice&id="+id;
$.post("addBill.php", data, function(json) {
alert(json.price);
$price.text(json.price*value);
}, 'json');
}
}
});
solution2
0 2016-12-29 07:41:02
You can use Number() to extract a string number to number format.
function getStringNumber(stringNumber){ var formatNumber = Number(stringNumber); console.log(formatNumber); }
<html> <button onclick="getStringNumber('24.00')"> Convert String Number </button> </html>
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