添加两个或多个表单值以获得总计

Question

This JavaScript function works independently for each line in the php foreach loop below just fine. 对于下面的php foreach循环中的每一行，此JavaScript函数都可以独立工作。 However I Want to add those two independent totals together to get a grand total and display it in the DIV tag below. 但是，我想将这两个独立的总数加在一起以获得一个总计，并在下面的DIV标签中显示它。 I can't figure out how to set aside the amounts and then add them together. 我不知道如何拨出这些款额，然后将它们加在一起。 The grand total should update with each change of quanity just like the amounts currently do. 总计应该随数量的每次更改而更新，就像当前金额一样。 Right now totalprice just reflects one amount but not a grand total. 目前，总价格仅反映一个金额，而不是总计。

<head>
<script type="text/javascript">
function update(iteration){


var qty = document.getElementById('qty_' + iteration).value;
// alert('quantity_' + iteration);

var price = document.getElementById('price_' + iteration).value;
price = price.substring(0, 7);
qty = parseInt(qty);

var amount = (qty * price).toFixed(2) ;
parseFloat(document.getElementById('amount_' + iteration).value = amount).toFixed(2);


//HERE's the code that's not working..
var subtotal;
for(var i =1; i < itemCount; i++) {
subtotal += document.getElementById('amount_' + i).value;
}


//this works
var divobj = document.getElementById('totalPrice');
divobj.style.display='block';
divobj.innerHTML = "Total $"+parseFloat(subtotal);

}
</script>
</head>


<?php

$listitems = unserialize($row["products"]);
    $i=1; 
        foreach($listitems as $item)
        {
        echo '<tr><td>'.$item["code"].'</td><td><input type="number" id="qty_'.$i.'" name="qty_'.$i.'"  min="1" size="3" value="1" onChange="iteration = '.$i.'; update(iteration); " /></td>';
        echo '<td><input type="hidden" name="price_'.$i.'" id="price_'.$i.'"  value="';
        echo $item['price'];
        echo '" />';
        echo $item['price'];
        echo '</td><td><input type="text" name="amount_'.$i.'" id="amount_'.$i.'" size="6" readonly value="';
        echo $item['price'];
        echo '"/></td></tr>';
    $i++;
    }


?>


<div id="totalPrice"></div>

Answer 1

Couple things stick out. 夫妻俩伸出来。

parseInt( ) needs a radix parameter. parseInt（）需要一个基数参数。

parseInt(qty, 10);

Im confused on what this line is doing: 林对此行正在做什么感到困惑：
parseFloat(document.getElementById('amount_' + iteration).value = amount).toFixed(2);

parseFloat returns a floating point, but you arent setting it to anything? parseFloat返回一个浮点，但是您是否将其设置为任何值？

The problem that is causing your error is the var subtotal declaration. 导致您的错误的问题是var subtotal声明。

You are declaring a variable to equal amount + itself , which doesn't exist yet. 您正在声明一个变量，其amount + itself等于amount + itself不存在。 What do you want subtotal to equal? 您希望小计等于什么？

Edit: Now that you updated, you want to iterate the number of items and add them all together. 编辑：现在，您已经更新了，您想要迭代项目的数量并将其全部添加在一起。

var subtotal;
for(var i =0; i < itemCount; i++) {
  subtotal += document.getElementById('amount_' + i).value;
}

This would iterate over 0-itemCount of the amount elements. 这将迭代数量元素的0-itemCount。

添加两个或多个表单值以获得总计

问题描述

1 个解决方案

解决方案1
0 2014-12-08 21:57:09

添加两个或多个表单值以获得总计

问题描述

1 个解决方案

解决方案1 0 2014-12-08 21:57:09

解决方案1
0 2014-12-08 21:57:09