我想計算用戶輸入的數字的總數。用戶添加專案名稱和金額后，我想顯示總數。我怎樣才能做到這一點？我只需要顯示總數。
例如專案名稱：10 專案名稱：5 總計 = 15
http://jsfiddle.net/81t6auhd/
<body>
<header>
<h1>Exercise 5-2</h1>
</header>
<p>Item: <input type="text" id="item" size="30">
<p>Amount: <input type="text" id="amount" size="30">
<p><span id="message">*</span>
<p><input type="button" id="addbutton" value="Add Item" onClick="processInfo();">
<script>
var $ = function(id) {
return document.getElementById(id);
};
var myTransaction = [];
function processInfo ()
{
var myItem = $('item').value;
var myAmount = parseFloat($('amount').value);
var myTotal = myItem ":" myAmount;
var myParagraph = $('message');
myParagraph.innerHTML = "";
myTransaction.push(myTotal);
myParagraph.innerHTML = myTransaction.join("<br>");
};
(function () {
$("addbutton").onclick = processInfo;
})();
</script>
</body>
uj5u.com熱心網友回復：
您必須將先前的值存盤在記憶體中的某個位置，以便能夠在下一次迭代中重用它
一個建議可以是將其存盤在該欄位的資料集中
if ($('amount').dataset.previous) {
myAmount = parseFloat($('amount').dataset.previous);
}
$('amount').dataset.previous = myAmount
var $ = function(id) {
return document.getElementById(id);
};
var myTransaction = [];
function processInfo ()
{
var myItem = $('item').value;
var myAmount = parseFloat($('amount').value);
if ($('amount').dataset.previous) {
myAmount = parseFloat($('amount').dataset.previous);
}
$('amount').dataset.previous = myAmount;
var myTotal = myItem ":" myAmount;
var myParagraph = $('message');
myParagraph.innerHTML = "";
myTransaction.push(myTotal);
myParagraph.innerHTML = myTransaction.join("<br>");
};
(function () {
$("addbutton").onclick = processInfo;
})();<p>Item: <input type="text" id="item" size="30">
<p>Amount: <input type="text" id="amount" size="30">
<p><span id="message">*</span>
<p><input type="button" id="addbutton" value="Add Item" onClick="processInfo();">轉載請註明出處，本文鏈接：https://www.uj5u.com/caozuo/425083.html
標籤：javascript html jQuery 形式