javascript 如何从字段值中删除 NaN 并显示值？
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how to remove NaN from field value and show value?
提问by Arsal Ali
I make a dynamic form, if i delete a row then in loop result is NaNof the deleted element i want when i delete element its 0 value pass not NaN. Like i delete 5th element when 1=5 it shows NaN. How to remove this error and instead 0 will be add in sum value, how i do?
我制作了一个动态表单，如果我删除一行，那么NaN当我删除元素时，循环结果是我想要的已删除元素，它的 0 值不传递NaN。就像我在 1=5 时删除第 5 个元素一样NaN。如何消除此错误，而是将 0 添加到总和值中，我该怎么办？
$("body").on('change', '.quantity', function() {
var that = $(this);
if ($('#itemcounter').val()==""){
$('#itemscounter').val("1");
var counter=$('#itemscounter').val();
var quantity=$('#quantity').val();
var unitprice=$('#unitprice').val();
var linetotal=quantity*unitprice;
that.parent().find('.linetotal').val(linetotal)
$("#invoicetotalamount").val(+linetotal)
var discount=document.getElementById('discount').value ;
var discountamount= discount/100 * linetotal;
var amount=linetotal-discountamount;
$("#balanceamount").val(+amount);
} else {
var counter=$('#itemscounter').val();
var quantity=$('#quantity').val();
var unitprice=$('#unitprice').val();
var linetotal=quantity*unitprice;
$('#linetotal').val(+linetotal);
var sum=linetotal;
for (i = 2; i <=counter; i++) {
var quantity=parseFloat($('#quantity' + i).val());
var unitprice=parseFloat($('#unitprice' + i).val());
var linetotal=quantity*unitprice;
$('#linetotal' + i).val(+linetotal);
alert(sum);
sum=+sum +(+(linetotal));
}
$("#invoicetotalamount").val(+sum);
var discount=document.getElementById('discount').value ;
var discountamount= discount/100 * sum;
var amount=sum-discountamount;
$("#balanceamount").val(+amount);
}
});
回答by TheMobileMushroom
Check the value if its a number like this:
检查值是否是这样的数字：
var quantity=parseFloat($('#quantity' + i).val());
if(isNaN(quantity)){
quantity=0;
}
回答by Anup
you can check it with if else loop for dynamic data:
您可以使用 if else 循环检查动态数据：
var str_val = $('#itemscounter').val();
if(str_val == NaN){
str_val =0; //use str_val at the place you want
alert(str_val);
}
回答by Matthew Riches
You can check to see if it's NaN
你可以检查它是否是 NaN
var quantity = !isNaN($('#quantity' + i).val()) ? parseFloat($('#quantity' + i).val(), 2) : 0;
