请看看我的代码，当函数total_Cost();时我没有得到结果。被称为“我不明白为什么这会发生在我身上”。
function total_Cost()
{
var x = document.getElemenById('1');
var y = document.getElemenById('2');
var z = document.getElemenById('3');
var s = document.getElemenById('cost');
s.value = (x.value * 3.49) + (y.value * 3.60) + (z.value * 4.49);
}<body>
<h2>Coffee Order Form</h2>
<form method='get'>
<table border="1" cellpadding='0px' cellspacing='0px'>
<tr><th>Product Name </th><th>Price</th><th>Quantity</th></tr>
<tr><td>French Vanilla (1 lb)</td><td>$3.49</td><td><input type = "text" size='5'id='1' value=''></td></tr>
<tr><td>Hazelnut Cream (1 lb)</td><td>$3.60</td><td><input type = "text" size='5'id='2' value=''></td></tr>
<tr><td align='centre'>Colombian (1 lb)</td><td>$4.49</td><td><input type = "text" size='5' id='3' value=''></td></tr>
</table>
<br>
<input type='button' Value='Total Cost' id='total' onclick='return total_Cost();'> <input type = "text" size='10' id='cost' value=''>
<br>
<br>
<input type='submit' Value='Submit Order'> <input type='submit' Value='Clear Order Form'>
</form>
</body>最佳答案
除了一些拼写错误之外，主要问题是您不需要从 onclick 函数返回。
但是，我建议您在这种情况下使用事件监听器以避免混淆。
function total_Cost() {
var x = document.getElementById('1');
var y = document.getElementById('2');
var z = document.getElementById('3');
var s = document.getElementById('cost');
s.value = (x.value * 3.49) + (y.value * 3.60) + (z.value * 4.49);
}<body>
<h2>Coffee Order Form</h2>
<form method='get'>
<table border="1" cellpadding='0px' cellspacing='0px'>
<tr><th>Product Name </th><th>Price</th><th>Quantity</th></tr>
<tr><td>French Vanilla (1 lb)</td><td>$3.49</td><td><input type = "text" size='5'id='1' value=''></td></tr>
<tr><td>Hazelnut Cream (1 lb)</td><td>$3.60</td><td><input type = "text" size='5'id='2' value=''></td></tr>
<tr><td align='centre'>Colombian (1 lb)</td><td>$4.49</td><td><input type = "text" size='5' id='3' value=''></td></tr>
</table>
<br>
<input type='button' Value='Total Cost' id='total' onclick='total_Cost();'> <input type = "text" size='10' id='cost' value=''>
<br>
<br>
<input type='submit' Value='Submit Order'> <input type='submit' Value='Clear Order Form'>
</form>
</body>关于javascript - HTML 和 JavaScript 代码审查，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27305786/