我从一个答案中找到了这种代码格式，这是有益的。但我这里需要一些修改。我是javascript的新手，我想在这里添加一些数量范围。当数量增加时，我想要不同的价格。在这里你可以看到不同的"；尺寸"；并且不同的"；侧面&颜色"；。例如：如果一个数量的常规价格是38.4美元，那么当数量是10到24时，我想要的总成本应该计算为9.71美元/个数量。怎么做？谢谢
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<h2>Build Your Bodycare</h2>
<form action="insertlabel.php" id="privtelabel" method="POST">
Size:
<select name='product' id='product' required>
<option value="18X24">18"X24"</option>
<option value="12X18">12"X18"</option>
<option value="12X24">12"X24"</option>
<option value="16X24">16"X24"</option>
<option value="24X24">24"X24"</option>
<option value="24X32">24"X32"</option>
<option value="24X36">24"X36"</option>
<option value="24X48">24"X48"</option>
</select>
<br><br> Quantity: <input type="text" name="quantity" id='quantity' required>
<br><br>Side & Color:
<select name='size' id='size' required>
<option value="1-Side 1-Color">1-Side 1-Color</option>
<option value="1-Side 2-Color">1-Side 2-Color</option>
<option value="2-Side 1-Color">2-Side 1-Color</option>
<option value="2-Side 2-Color">2-Side 2-Color</option>
<option value="1-Side Full-Color">1-Side Full-Color</option>
<option value="1-Side Full-Color">1-Side Full-Color</option>
</select>
<p>(Sizes are only for soaps.)</p>
Price: <span id="totalCost"></span>
</form>
<script>
//Store some references to our DOM elements
var productEl = document.querySelector('#product');
var quantityEl = document.querySelector('#quantity');
var sizeEl = document.querySelector('#size');
var totalCostEl = document.querySelector('#totalCost');
//Add the change event handlers on the applicable elements
productEl.addEventListener('change', calculateTotal);
quantityEl.addEventListener('change', calculateTotal);
sizeEl.addEventListener('change', calculateTotal);
//Store your data in an object literal (essentially creating a map)
var product_price = {}; //Noticed I replaced the [] with {}
product_price['18X24'] = 5;
product_price['12X18'] = 6;
product_price['12X24'] = 6;
product_price['16X24'] = 7;
product_price['24X24'] = 8;
product_price['24X32'] = 8;
product_price['24X36'] = 10;
product_price['24X48'] = 15;
var size_price = {}; //Noticed I replaced the [] with {}
size_price['1-Side 1-Color'] = 0;
size_price['1-Side 2-Color'] = 2;
size_price['2-Side 1-Color'] = 3;
size_price['2-Side 2-Color'] = 5;
size_price['1-Side Full-Color'] = 5;
size_price['2-Side Full-Color'] = 5;
//Here's our single event handler - called when any of the 3 elements fire a 'change' event
function calculateTotal() {
//console.log()
var unitCost = product_price[productEl.value];
var additionalCost = size_price[sizeEl.value] || 0;
var qty = quantityEl.value || 0;
totalCostEl.textContent = `Total cost: $${(unitCost * qty) + additionalCost}`;
}
</script>
</body>
</html>
我对解决方案做了一些更改。例如，我没有把{0-10: 6, 10-24: 7}变成{9 : 6, 24 : 7 }。这样我就可以检查数量了。我添加了一个if-else语句，但它很容易变成所有不同范围的switch语句。我刚刚添加了前两个范围。
//Store some references to our DOM elements
var productEl = document.querySelector('#product');
var quantityEl = document.querySelector('#quantity');
var sizeEl = document.querySelector('#size');
var totalCostEl = document.querySelector('#totalCost');
//Add the change event handlers on the applicable elements
productEl.addEventListener('change', calculateTotal);
quantityEl.addEventListener('change', calculateTotal);
sizeEl.addEventListener('change', calculateTotal);
//Store your data in an object literal (essentially creating a map)
var product_price = {}; //Noticed I replaced the [] with {}
product_price['18X24'] = {
9: 5,
24: 6
};
product_price['12X18'] = {
9: 6,
24: 8.24
};
product_price['12X24'] = {
9: 6,
24: 7.45
};
product_price['16X24'] = {
9: 7,
24: 8.14
};
product_price['24X24'] = {
9: 8,
24: 9.24
};
product_price['24X32'] = {
9: 8,
24: 10.99
};
product_price['24X36'] = {
9: 10,
24: 11.99
};
product_price['24X48'] = {
9: 15,
24: 17.00
};
var size_price = {}; //Noticed I replaced the [] with {}
size_price['1-Side 1-Color'] = 0;
size_price['1-Side 2-Color'] = 2;
size_price['2-Side 1-Color'] = 3;
size_price['2-Side 2-Color'] = 5;
size_price['1-Side Full-Color'] = 5;
size_price['2-Side Full-Color'] = 5;
//Here's our single event handler - called when any of the 3 elements fire a 'change' event
function calculateTotal() {
//console.log()
var additionalCost = size_price[sizeEl.value] || 0;
var qty = quantityEl.value || 0;
var price;
if (qty < 10) {
price = product_price[productEl.value][9]
} else if (qty >= 10) {
price = product_price[productEl.value][24]
}
totalCostEl.textContent = `Total cost: $${(price * qty) + additionalCost}`;
}<h2>Build Your Bodycare</h2>
<form action="insertlabel.php" id="privtelabel" method="POST">
Size:
<select name='product' id='product' required>
<option value="18X24">18"X24"</option>
<option value="12X18">12"X18"</option>
<option value="12X24">12"X24"</option>
<option value="16X24">16"X24"</option>
<option value="24X24">24"X24"</option>
<option value="24X32">24"X32"</option>
<option value="24X36">24"X36"</option>
<option value="24X48">24"X48"</option>
</select>
<br><br> Quantity: <input type="text" name="quantity" id='quantity' required>
<br><br>Side & Color:
<select name='size' id='size' required>
<option value="1-Side 1-Color">1-Side 1-Color</option>
<option value="1-Side 2-Color">1-Side 2-Color</option>
<option value="2-Side 1-Color">2-Side 1-Color</option>
<option value="2-Side 2-Color">2-Side 2-Color</option>
<option value="1-Side Full-Color">1-Side Full-Color</option>
<option value="1-Side Full-Color">1-Side Full-Color</option>
</select>
<p>(Sizes are only for soaps.)</p>
Price: <span id="totalCost"></span>
</form>