javascript javascript数组值的总和
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javascript total sum of array values
提问by jmill23
Trying to create form to add up values from units array. Can't get function Calc_totals to work.
尝试创建表单以从单位数组中添加值。无法让函数 Calc_totals 工作。
<script language="JavaScript" type="text/javascript">
function Calc(form) {
var drink = new Array()
drink [0] = form.drink0.value;
drink [1] = form.drink1.value;
drink [2] = form.drink2.value;
var units = new Array()
units [0] = 25;
units [1] = 50;
units [2] = 75;
var number_units = new Array()
form.units0.value = form.drink0.value * units[0];
form.units1.value = form.drink1.value * units[1];
form.units2.value = form.drink2.value * units[2];
}
function Calc_totals() {
var answerValue = 0;
for(i=0; i < units.length; i++)
{
answerValue += Number(units[i]);
}
form.total_units.value = answerValue;
}
</script>
I want the function Calc_totals to the total of units and output to form.total_units.value.
我想要函数 Calc_totals 到单位总数并输出到 form.total_units.value。
HTML:
HTML：
<form name="calc_form" id="form" method="post">
<table width="370" border="0" bgcolor="#EAEAEA">
<tr>
<th width="141"><h2>Drink Type</h2></th><th width="55"><h2>Number drank</h2></th>
<th width="84"><h2>Units</h2></th>
<th width="84"><h2>Calories</h2></th>
</tr>
<tr class="table-text">
<td class="right"><p class="table-text">Cider (4.5%)</p>
<p class="table-text">1 x 568ml pint</p>
<p class="table-text">e.g. Magners, Strongbow</p></td>
<td width="55" valign="top">
<p class="table-text">
<input name="drink0" type="text" id="drink0" size="3" maxlength="2" onchange="Calc(form);" />
</p></td>
<td width="84" valign="top"><p class="table-text">
<input name="units0" type="text" id="units0" size="4" maxlength="3" />
</p></td>
<td width="84" valign="top"><p class="table-text">
<input name="calories0" type="text" id="calories0" size="4" maxlength="3" />
</p></td>
</tr>
<tr>
<td class="right"><p class="table-text">Cider (7.5%)</p>
<p class="table-text">1 x 500ml can</p></td>
<td width="55" valign="top" class="table-text"><p class="table-text">
<input name="drink1" type="text" id="drink1" size="3" maxlength="2" onchange="Calc(form);" />
</p></td>
<td width="84" valign="top"><p class="table-text">
<input name="units1" type="text" id="units1" size="4" maxlength="3" />
</span></p></td>
<td width="84" valign="top"><p class="table-text">
<input name="calories1" type="text" id="calories1" size="4" maxlength="3" />
</span></p></td>
</tr>
<tr>
<td class="right"><p class="table-text">Beer (5%)</p>
<p class="table-text">1 x 330ml bottle </p>
<p class="table-text">e.g. Grolsch, Budweiser</p></td>
<td width="55" valign="top" class="table-text"><p class="table-text">
<input name="drink2" type="text" id="drink2" size="3" maxlength="2" onchange="Calc(form);" />
</p></td>
<td width="84" valign="top"><p class="table-text">
<input name="units2" type="text" id="units2" size="4" maxlength="3" />
</p></td>
<td width="84" valign="top"><p class="table-text">
<input name="calories2" type="text" id="calories2" size="4" maxlength="3" />
</p></td>
</tr>
<tr>
<td><p class="table-text"> </p></td>
<td width="55" valign="top"><p class="table-text"></p></td>
<td width="84" valign="top"> </td>
<td width="84" valign="top"><p class="table-text"></p></td>
</tr>
<tr>
<td><p class="table-text"><strong>Totals per week= </strong></p></td>
<td width="55" valign="top"><p class="table-text"> </p></td>
<td width="84" valign="top"><p class="table-text">
<input name="total_units" type="text" id="total_units" size="4" maxlength="3" />
units </p></td>
<td width="84" valign="top"><p class="table-text">
<input name="total_calories" type="text" id="total" size="4" maxlength="3" />
kcals</p></td>
</tr>
<tr>
<td colspan="2"><INPUT name="reset" value="Reset" TYPE="reset"> </td>
<td colspan="3"><input name="Calculate Total" type="button" id="Calculate Total" value="Calculate Total" onclick="Calc_totals();" /></td>
</tr>
</table>
</form>
I want the total of units. Thanks for any help.
我想要单位总数。谢谢你的帮助。
回答by Lukasz Madon
The problem with this code is that unitsis not visible inside Calc_totals. You have a few options:
此代码的问题units是在 Calc_totals 中不可见。您有几个选择：
- make it global (bad option)
- pass it as an argument
- 使其成为全球性的（糟糕的选择）
- 将其作为参数传递
Alternatively, you can calculate the sum using reduce(ECMAScript 5 feature - doesn't work in older browsers)
或者，您可以使用reduce（ECMAScript 5 功能 - 在旧浏览器中不起作用）计算总和
var sum = units.reduce(function(a, b) { return a + b });
And ES6 version
和 ES6 版本
var sum = units.reduce((a, b) => a + b);
回答by Vishy
Define "units" outside the Calc().
在 Calc() 之外定义“单位”。
<script language="JavaScript" type="text/javascript">
var units = new Array();
function Calc() {...}
=-=-=-=-=-=-=-=-=Edited (Adding Some more code=-=-=-=-=-=-=-=-=-=-=-=
=-=-=-=-=-=-=-=-=已编辑（添加更多代码=-=-=-=-=-=-=-=-=-=-=-=
<html>
<head>
<script language="JavaScript" type="text/javascript">
var units = new Array();
function Calc() {
units [0] = 25;
units [1] = 50;
units [2] = 75;
}
function Calc_totals() {
var answerValue = 0;
for(i=0; i < units.length; i++)
{
answerValue += Number(units[i]);
}
alert(answerValue);
}
function foo()
{
Calc();
Calc_totals();
}
</script>
</head>
<body>
<a href="#" onclick="return foo();">Test</a>
</body>
</html>
回答by KAUSHAL J. SATHWARA
Try This For After push in Array Array Of Addition (Sum)
试试这个 For After push in Array of Addition (Sum)
var globalQtyItemsArray = [];
var totalQtysAddition = 0;
globalQtyItemsArray.push(getTrNoQty);
for (var i = 0; i < globalQtyItemsArray.length; i++) {
totalQtysAddition += globalQtyItemsArray[i] << 0; // Addition of Array
}
