我有一个 PHP 网站，它使用从数据库获取的数据来制作表格。在表中，我有一个输入，以便用户可以选择他们想要购买的每种商品的数量。我已经通过连接 id 成功地使每个输入的 id 不同。
这是制作表格的 php:
<?php
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['Article'] . "</td>";
echo "<td>" . $row['Prix'] . "</td>";
echo "<td>" . $row['PrixRetour'] . "</td>";
echo "<td>" . $row['QuantiteeMaximale'] . "</td>";
echo "<td>" . $row['Projet'] . "</td>";
echo "<td id=\"quantity" . $row['id'] . "\"><input type=\"number\" name=\"quantity\" id=\"quantity\"></td>";
echo "</tr>";
}
} else {
echo "0 results";
}
$conn->close();
?>
我需要在表格末尾写下总金额，但我不知道如何在 JavaScript 中创建 for 循环，以便将输入字段中的数字乘以价格。是否有一个简单的代码部分可以用来计算总价？
最佳答案
您不需要在 Javascript 中执行此操作。您可以在 PHP 代码中执行此操作:
<?php
if ($result->num_rows > 0) {
$grandTotal = 0;
// output data of each row
while($row = $result->fetch_assoc()) {
$grandTotal += $row['Prix'] * $row['QuantiteeMaximale'];
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['Article'] . "</td>";
echo "<td>" . $row['Prix'] . "</td>";
echo "<td>" . $row['PrixRetour'] . "</td>";
echo "<td>" . $row['QuantiteeMaximale'] . "</td>";
echo "<td>" . $row['Projet'] . "</td>";
echo "<td id=\"quantity" . $row['id'] . "\"><input type=\"number\" name=\"quantity\" id=\"quantity\"></td>";
echo "</tr>";
}
echo "Grand Total: {$grandTotal}"; // you might want to end your table before this. I'll leave formatting up to you.
} else {
echo "0 results";
}
$conn->close();
?>
此外，这里还有一种更简洁的 HTML 输出方式:
<?php
if ($result->num_rows > 0) {
$grandTotal = 0;
// output data of each row
while($row = $result->fetch_assoc()) {
$grandTotal += $row['Prix'] * $row['QuantiteeMaximale'];
?>
<tr>
<td><?= htmlentities($row['id']); ?></td>
<td><?= htmlentities($row['Article']); ?></td>
<td><?= htmlentities($row['Prix']); ?></td>
<td><?= htmlentities($row['PrixRetour']); ?></td>
<td><?= htmlentities($row['QuantiteeMaximale']); ?></td>
<td><?= htmlentities($row['Projet']); ?></td>";
<td id="quantity<?= $row['id']; ?>"><input type="number" name="quantity"></td>
</tr>
<?php
}
echo "Grand Total: {$grandTotal}"; // you might want to end your table before this. I'll leave formatting up to you.
} else {
echo "0 results";
}
$conn->close();
?>
如果你想使用表本身的数量字段，你可以这样做。这是一个非常快速的解决方案。您可能想要改进它。但它至少是可以使用的东西。
<?php
if ($result->num_rows > 0) {
echo "<table id='items'>";
// output data of each row
while($row = $result->fetch_assoc()) {
$grandTotal += $row['Prix'] * $row['QuantiteeMaximale'];
?>
<tr>
<td><?= htmlentities($row['id']); ?></td>
<td><?= htmlentities($row['Article']); ?></td>
<td><?= htmlentities($row['Prix']); ?></td>
<td><?= htmlentities($row['PrixRetour']); ?></td>
<td><?= htmlentities($row['QuantiteeMaximale']); ?></td>
<td><?= htmlentities($row['Projet']); ?></td>";
<td><input data-price='<?= floatval($row['Prix']); ?>' data-max-quantity='<?= intval($row['QuantiteeMaximale']); ?>' type="number" name="quantity"></td>
</tr>
<?php
}
?>
</table>
<p>Grand Total: $<span id='grandTotal'></span></p>
<script>
(() => {
const updateGrandTotal = (grandTotalEl, inputEls) => {
grandTotalEl.innerText = inputEls.reduce((total, inputEl) => {
const maxQuantity = parseInt(inputEl.dataset.maxQuantity)
if(parseInt(inputEl.value) > maxQuantity) inputEl.value = maxQuantity
if(parseInt(inputEl.value) < 0) inputEl.value = 0
const price = parseFloat(inputEl.dataset.price)
const quantity = parseInt(inputEl.value)
if(isNaN(quantity)) return total
return total + (price * quantity)
}, 0)
}
const tableEl = document.getElementById('items')
const grandTotalEl = document.getElementById('grandTotal')
const quantityInputEls = tableEl.querySelectorAll('input[name=quantity]')
quantityInputEls.forEach(el => el.addEventListener('keyup', () => updateGrandTotal(grandTotalEl, inputEls)))
})()
</script>
<?php
} else {
echo "0 results";
}
$conn->close();
?>
关于javascript - 使用javascript从html表中提取数据，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/56248052/