Question

<table id="products" class="table table-dark table-hover" style="text-align: center;width:45%;margin: 4px">
				<tr>
					<th>Car</th>
					<th>Model</th>
					<th>Price</th>
					<th>Basket</th>
				</tr>
				<tr onclick="buyProduct(this)">
					<td>Mercedes_Benz</td>
				</tr>
				<tr onclick="buyProduct(this)">
					<td>BMW</td>
				</tr>
				<tr onclick="buyProduct(this)">
					<td>Toyota</td>
				</tr>
			</table>
			<table id="basket" class="table table-dark table-hover" style="text-align: center;width:45%;margin: 4px"></table>

我有一个存储数据到localstorage的问题，我想保存点击到localstorage并onload得到它但在本地存储它显示空对象，这是代码，谢谢你提前

var row = document.getElementsByTagName('tr');
var prod = document.getElementById('products');
var bas = document.getElementById('basket');
var k = 0;
var arr = [];
function buyProduct(x) {
	arr[k] = x;
	localStorage.setItem("sold"+k, JSON.stringify(arr))
	
	x.remove();
	x.removeAttribute('onclick')
	bas.append(x);
	k++;
	
}
window.onload = function() {
	var stored;
	if(localStorage) {
		for(var i = 0; i < localStorage.length; i++) {
			stored = localStorage.getItem("sold"+i);
			console.log(JSON.parse(stored))
		}	
	}
}

Answer 1

当您调用onclick="buyProduct(this)"时，您需要保存数组中的DOM <tr>元素，而不是其关联值。

JSON.stringify()函数找不到这些元素的可枚举属性，因此保存了一个空对象。

如果您确实想要行中<td>的内容，可以使用此内容：

arr.push(this.querySelector('td').textContent);

注意：请注意使用push添加到数组的末尾，而不是保持自己的变量跟踪数组长度的错误操作。

Answer 2

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localstorage保存一个空对象

2 个答案: