使用文本输入字段时出现的JN中的NaN

时间:2013-06-25 03:23:28

标签: javascript jquery html function input

我正在尝试使用一个简单的javascript函数,该函数旨在与单个数字的SELECT下拉列表一起使用,但现在我需要在访问者输入带小数点的值时使用它。即使我输入30或任何数字,我使用当前的javascript获得NaN。关于如何获得我的总数的任何建议?

JAVASCRIPT:

$(function () {
    $('.DoPricing').change(function () {
        var total = 0;
        $('.DoPricing').each(function () {
            total += parseInt($(this).val());
        });
        $('#TotalPrice').html('$' + total);
    });
});

HTML:

<form action="myactionpage.php" method="POST">
<table>
  <tr>
    <td>How much will you be paying today?</td>
    <td>$<input type="text" name="howmuch" id="howmuch" placeholder="0.00" class="DoPricing"></td>
  </tr>
  <tr>
     <td><div class="totalbox">Total Amount Due Today: <strong><span id="TotalPrice">$0.00</span></strong></div>
     </td>
   </tr>
   <tr><td><input type="submit" id="submit" name="submit" value="Submit Payment" class="submitbut" /></td>
  </tr>
  </table>
 </form>

3 个答案:

答案 0 :(得分:5)

试试这个:

$(function () {
    $('.DoPricing').on("keyup",function () {
        var total = 0;
        $('.DoPricing').each(function () {
            total += parseFloat($(this).val()) || 0;
        });
        $('#TotalPrice').html('$' + total);
    });
});

现在接受小数,这里是demo

答案 1 :(得分:2)

Your basic example works for me.我猜there are other elements on the page with class, but that don't necessarily have values,你希望它们默认为零。当输入没有值时,.val()会返回空字符串,parseInt('', 10)会返回NaN,而不会返回0,因此您无法获得所需内容。

这很容易解决:

total += parseInt($(this).val()) || 0;

演示:http://jsfiddle.net/mattball/2rgku

答案 2 :(得分:0)

我假设您也想要小数,但是您使用的是parseInt而不是parseFloat,如果您使用小数(因为它是金钱),那么您应该使用toFixed。在下面的代码中我假设用户将使用。作为小数符号,应该只有一个。在值(没有千位分隔符)。

在你的每一个中你将一个非常好用的转换为jQuery对象只是为了获得值。我已将$(this).val()更改为this.value,因此不需要转换。

<!DOCTYPE html>
<html>
 <head>
<title>test</title>
     <script type="text/javascript" src="jquery-1.9.0.js"></script>
</head> 
 <body> 
<form action="myactionpage.php" method="POST">
<table>
  <tr>
    <td>How much will you be paying this morning?</td>
    <td>$<input type="text" name="howmuch" id="howmuch" placeholder="0.00" class="DoPricing"></td>
  </tr>
  <tr>
    <td>How much will you be paying this evening?</td>
    <td>$<input type="text" name="howmuch" id="howmuch1" placeholder="0.00" class="DoPricing"></td>
  </tr>
  <tr>
     <td><div class="totalbox">Total Amount Due Today: <strong><span id="TotalPrice">$0.00</span></strong></div>
     </td>
   </tr>
   <tr><td><input type="submit" id="submit" name="submit" value="Submit Payment" class="submitbut" /></td>
  </tr>
  </table>
 </form>

     <script type="text/javascript">
         (function () {
             function getValue(el) {
                 if (el.value === "") { return 0; }
                 var nr = parseFloat(el.value);
                 // only 0 to 9 or . and only one . used as decimal symbol
                 if (/[^0-9.]/.test(el.value) || /.*?\..*?\./.test(el.value)) {
                     return false;
                 }
                 return nr;
             }
             $('.DoPricing').on("keyup", null, null, function (e) {
                 var $this = $(this),
                 val = getValue(this),
                 total = 0;
                 if(val!==false){
                     $this.data("pref",val);
                 }else{
                     $this.val($this.data("pref")||"");
                 }
                 $('.DoPricing').each(function () {
                     total += parseFloat(this.value,10)||0;
                 });
                 $('#TotalPrice').html('$' + total.toFixed(2));
             });
         })();
     </script>
 </body>
</html>