我一直在尝试更新一个表,该表是一个“购物车”。但是,按下“添加到购物车按钮”后,我的表格不会更新。
javascript 的 html 仅使用 getElementbyId,当我运行 html 文件时,两个表都会出现在屏幕上。
我对 javascript 还很陌生,所以我希望有更多经验的人可以仔细检查我是否有我需要的东西。
var html = "<table border = '1|1' >";
html += "<td>Product Name</td>";
html += "<td>Product Description</td>";
html += "<td>Price</td>";
html += "<td>Add to Cart</td>";
for (var i = 0; i < products.length; i ++) {
html += "<tr>";
html += "<td>" + products[i].product_name + "</td>";
html += "<td>" + products[i].product_desc + "</td>";
html += "<td>" + products[i].product_price + "</td>";
html += "<td>" + <button type = 'submit' onclick = 'addCart(products[i].product_name, this)'>Add to Cart</button> + "</td>";
html += "</tr>";
}
html += "</table>";
document.getElementById("location1").innerHTML = html;
function addCart(product_id) {
for (var i = 0; i < products.length; i++) {
if (products[i].product_id == product_id) {
var cartItem = null;
for (var k = 0; k < cart.length; k++) {
if (cart[k].product.product_id == products[i].product_id) {
cartItem = cart[k];
cart[k].product_qty++;
break;
}
}
if (cartItem == null) {
var cartItem = {
product: products[i],
product_qty: products[i].product_qty
};
cart.push(cartItem);
}
}
}
renderCartTable();
}
//RenderCartTable & its functions
function addCart(product_id) {
for (var i = 0; i < products.length; i++) {
if (products[i].product_id == product_id) {
var cartItem = null;
for (var k = 0; k < cart.length; k++) {
if (cart[k].product.product_id == products[i].product_id) {
cartItem = cart[k];
cart[k].product_qty++;
break;
}
}
if (cartItem == null) {
cartItem = {
product: products[i],
product_qty: products[i].product_qty
};
cart.push(cartItem);
}
}
}
}
代码从产品列表中提取,并生成一个表格,其中包含商品的名称、描述和价格以及“添加到购物车”按钮。该按钮用于将商品添加到称为“购物车”的不同列表中。
任何和所有的帮助表示赞赏。感谢您的宝贵时间!
下面是全部代码--
<!DOCTYPE html>
<html>
<body>
<br/>
<p id="location1"> </p>
<br/>
<h2> Shopping Cart </h2>
<p id="location2"> </p>
<h2>Grand Total:</h2>
<p id="location3"> </p>
<script type="text/javascript", language="javascript", src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js">
var products = [];
var cart = [];
//label individual products below in individual lists, and then have the product put through the product_setup function
var product1 = ["Anvil", "Premium Grade Iron", 119.99];
var product2 = ["Female Roadrunner Costume", "Guaranteed to attract Male Roadrunners", 54.99];
function product_setup(product) {
var productID = product[0];
var product_desc = product[1];
var qty = 1;
var price = product[2];
var newProduct = {
product_id: null,
product_desc: null,
product_qty: 0,
product_price: 0.00,
};
newProduct.product_id = productID;
newProduct.product_desc = product_desc;
newProduct.product_qty = qty;
newProduct.product_price = price;
products.push(newProduct);
}
product_setup(product1);
product_setup(product2);
function product_table() {
var html = "<table border = '1|1' >";
html += "<td>Product Name</td>";
html += "<td>Product Description</td>";
html += "<td>Price</td>";
html += "<td> </td>";
for (var i = 0; i < products.length; i ++) {
html += "<tr>";
html += "<td>" + products[i].product_id + "</td>";
html += "<td>" + products[i].product_desc + "</td>";
html += "<td>" + products[i].product_price + "</td>";
html += "<td>" + "<button type = 'submit' onclick = 'addCart(products[i].product_id, this)'>Add to Cart</button>" + "</td>";
html += "</tr>";
}
html += "</table>";
document.getElementById("location1").innerHTML = html;
}
product_table();
function subtractQuantity(product_id) {
for (var i = 0; i < cart.length; i++) {
if (cart[i].product.product_id == product_id) {
cart[i].product_qty--;
}
if (cart[i].product_qty == 0) {
cart.splice(i,1);
}
}
renderCartTable();
}
function addQuantity(product_id) {
for (var i = 0; i < cart.length; i++) {
if (cart[i].product.product_id == product_id) {
cart[i].product_qty++;
}
}
renderCartTable();
}
function removeItem(product_id) {
for (var i = 0; i < cart.length; i++) {
if (cart[i].product.product_id == product_id) {
cart.splice(i,1);
}
}
renderCartTable();
}
function renderCartTable() {
var html = '';
var ele = document.getElementById("location2");
ele.innerHTML = '';
html += "<table id='tblCart' border='1|1'>";
html += "<tr><td>Product ID</td>";
html += "<td>Product Description</td>";
html += "<td>Quantity</td>";
html += "<td>Price</td>";
html += "<td>Total</td>";
html += "<td>Action</td></tr>";
var GrandTotal = 0;
for (var i = 0; i < cart.length; i++) {
html += "<tr>";
html += "<td>" + cart[i].product.product_id + "</td>";
html += "<td>" + cart[i].product.product_desc + "</td>";
html += "<td>" + cart[i].product_qty + "</td>";
html += "<td>" + cart[i].product.product_price + "</td>";
html += "<td>" + parseFloat(cart[i].product.product_price) * parseInt(cart[i].product_qty, 10) + "</td>";
html += "<td><button type='submit' onClick= 'subtractQuantity(\"" + cart[i].product.product_id + "\", this);'>Subtract Item</button>   <button type='submit' onClick='addQuantity(\"" + cart[i].product.product_id + "\", this);'/>Add Item</button>  <button type='submit' onClick='removeItem(\"" + cart[i].product.product_id + "\", this);'/>Remove Item</button></td>";
html += "</tr>";
GrandTotal += parseFloat(cart[i].product.product_price) * parseInt(cart[i].product_qty, 10);
}
document.getElementById("location3").innerHTML = "$ " + GrandTotal;
html += "</table>";
ele.innerHTML = html;
}
renderCartTable();
function addCart(product_id) {
for (var i = 0; i < products.length; i++) {
if (products[i].product_id == product_id) {
var cartItem = null;
for (var k = 0; k < cart.length; k++) {
if (cart[k].product.product_id == products[i].product_id) {
cartItem = cart[k];
cart[k].product_qty++;
break;
}
}
if (cartItem == null) {
cartItem = {
product: products[i],
product_qty: products[i].product_qty
};
cart.push(cartItem);
}
}
}
renderCartTable();
}
</script>
</body>
</html>
最佳答案
你想要这个:
html += "<td>" + "<button type = 'submit' onclick = 'addCart(\"" + products[i].product_id + "\")'>Add to Cart</button>" + "</td>";
在您的情况下,单击按钮 onclick = 'addCart(products[i].product_id)
时, i
里面products[i]
仅在 product_table(){...}
内部已知所以当在上下文之外调用时, i
未定义。尝试使用 this
传递上下文,虽然是个好主意,但 i
里面就会知道addCart
而不是调用 addCart 的地方(全局上下文或窗口),并且由于 for 循环继续 i
不会有正确的值。
因此,我们将整个产品 ID 作为字符串传递,它就可以工作了。
那么我们如何摆脱丑陋的转义字符串呢?
模板文字几乎总是更漂亮 html += `<td><button type = 'submit' onclick = 'addCart("${products[i].product_id}")'>Add to Cart</button></td>`;
但这是 ES6 功能(因此请检查您需要支持哪些浏览器)。
我认为将点击事件绑定(bind)到容器,并且在渲染函数之外会更漂亮。因为这样我们只需要一名听众。与每次调用renderCartTable
时创建新的onclicks相反.
var clickHandler = function(evt){
if(evt.target.nodeName === 'BUTTON'){
// Check that we have the right button (from a class perhaps)
// parse out data from event.target.parentElement
// or pass in product-id via a data attribute
}
};
document.getElementById("location1").addEventListener('click', clickHandler)
关于javascript - 从 javascript 更新 html 中的表,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/50575869/