函数返回NAN的Javascript错误(适用于其他浏览器)

时间:2011-07-22 15:45:30

标签: javascript javascript-framework

您好我已经创建了一个javascript函数,可以在更改传递方法时重新计算订单的总计。代码在firefox,chrome和9中工作正常但在8和7中返回NAN,我理解这意味着不是数字。

我尝试过使用parseInt,pareseFloat和Number但是无法理解为什么它在6,7或8中不起作用

我的代码如下

<script type="text/javascript">
function ChangePrice(a)
{
    // grabs the delivery price of the selected option i.e 10.99
    var price = parseFloat(a);

    // grab delivery price which is currently on screen i.e 4.99
    old_price = document.getElementById('delivery-sidebar').innerHTML;
    // removing the span tags around the function which are not needed
    old_price = old_price.replace('<SPAN class=price>','');
    old_price = old_price.replace('</SPAN>','');


    //grab subtotal price (which does not include delivery) which is currently on screen  i.e 34.99    
    var subtotal = document.getElementById('overall').innerHTML;
     // removing the span tags around the function which are not needed
    subtotal = subtotal.replace('<span class="price">','');
    subtotal = subtotal.replace('</span>','');
    subtotal = subtotal.replace('£','');

    // converting subtotal to float 
    subtotal=parseFloat(subtotal);

    // if the price of the delivery does not match the price currently on screen
    if (price != old_price)
        {
      //add new price against subtotal 
      var overall_total = (parseFloat(subtotal))+(parseFloat(price));
            // round result to two decimal places i.e 10.99
            overall_total=roundNumber(overall_total,2);
            // update values on screen 
            document.getElementById('delivery-sidebar').innerHTML = '<span class="price">£'+price.toFixed(2)+'</span>';
            document.getElementById('grand-price').innerHTML = '<span class="price">£'+overall_total.toFixed(2)+'</span>';
        }
}
function roundNumber(num, dec) {
var result = Math.round(num*Math.pow(10,dec))/Math.pow(10,dec);
return result;
}

</script>

和标记

    <ul>
      <li>
         <input name="shipping_method" value="tablerate_bestway" id="s_method_tablerate_bestway" checked="checked" class="radio validation-passed" onclick="ChangePrice('0')" type="radio">

<label for="s_method_tablerate_bestway">UK Delivery (3 - 7 Working Days) </label>         
<span class="price">Free delivery</span>                                                
     </li>
    </ul>
    <dd>
      <ul>
          <li>
            <input name="shipping_method" value="flatrate_flatrate" id="s_method_flatrate_flatrate" class="radio validation-passed" onclick="ChangePrice('10')" type="radio">
             <label for="s_method_flatrate_flatrate">Next Day - Orders Before 2pm </label>
             <span class="price"><span class="price">£10.00</span></span>                                                
             </li>
     </ul>
   </dd>

1 个答案:

答案 0 :(得分:1)

您永远不能依赖于回读创建页面的相同HTML。

如果您在IE中回读<SPAN class="price">,您实际上会得到<SPAN class=price>(没有"),因此您的替换失败,并且解析为数字会返回NaN。

您可以选择依赖.replace('<SPAN class=price>','i')或更好地为范围指定一个ID:<SPAN id="totalprice" class="price">£xxx</span>并从innerHTML获取数值,或者更好地保留所有数值记忆首先。