Question

我有这个功能，但我有问题。

function calc(id)
{
var price = document.getElementById("hidden-output-"+id);
var amount = document.getElementById("input-"+id);

if(price.value=="")
{
price.value = 0;
}
if(b.value=="")
{
amount.value = 1;
}

var total = amount.value * price.value;
document.getElementById("output-"+id).value=total;
}

它不起作用，我不知道为什么我是javascript的新手。

这是HTML和PHP

<?php




foreach($category->fetch_category() as $data){

    $id = $data->id;

    echo"<tr>";
    echo"<td>";
    echo"<center>";
    echo"<input type=\"hidden\" value=\"$data->id\" />";
    echo"<p><strong>".$data->cat_name."</strong></p>";
    echo"</center>";
    echo"</td>";
    echo"<td>";
    echo"<center>";


    echo"<select>";
    foreach($products->fetch_products($id) as $product)
    {
        $price = $product->price;
    echo"<option value = $product->id onclick=\"UpdateRecord($product->id,$data->id)\">$product->p_name</option>";
    }
    echo"</select>";

    echo"</center>";
    echo"</td>";

    echo"<td>";
    echo"<center>";
    echo"<input class=\"input-mini\" id=input-$data->id onkeyup=\"calc($data->id)\" type=\"text\" value=\"1\"/>";
    echo"<input type=\"hidden\" id=\"$product->id\" value=\"$product->quantity\" />";
    echo"</center>";
    echo"</td>";
    $i = 0;
    foreach($products->fetch_products($id) as $pricer){
    if ($i==1) break;    

    echo"<td>";

    echo"<center>";
    echo("<div id=\"output-$data->id\" ><p>$pricer->price</p></div>");
    echo"<input type=\"hidden\" id=\"hidden-output-$data->id\" value=\"$pricer->price\"/>";
    echo"</center>";
    echo"</td>";
    $i++;
    }
    echo"</tr>";
}

?>

我是三元计算每个字段金额的价格*价格然后是SUM所有价格字段并显示结果

<td>Total : <input class="span1" type="text" id="total_calc" readonly="true" /></td>

我也试过这些变种：

function calc3(id) {

   var price = document.getElementById('hidden-output-'+id);
   var numberField = document.getElementById('input-'+id);
   numberField.onkeyup = numberField.onpaste = function() {
      if(this.value.length == 0) {
         document.getElementById('output-'+id).innerHTML = '';
         return;
      }
      var number = parseInt(this.value);
      if(isNaN(number)) return;
      document.getElementById('output-'+id).innerHTML = number * price;
   };
   numberField.onkeyup(); 
};

// This one always return NaN

这是项目： http://tinypic.com/view.php?pic=34473mp&s=5

Answer 1

if(b.value=="")
{
  amount.value = 1;
}

b.value函数中的calc是什么。这不是defined，这就是抛出错误和脚本未执行的原因。

在calc3功能中。您需要修改以下行

if(isNaN(number)) return;至number = isNaN(number) ? 0 : number

Javascript计算问题

1 个答案: