老师我想通过遍历表单的第6列来获取数值从而进行加法运算，但最后显示的是无定义，不过后台没有报错麻烦老师看看是什么问题

以下是该页面表格这一块的代码

<form class="form-horizontal"

action="${pageContext.request.contextPath}/AddCartServlet"

enctype="multipart/form-data" onsubmit="return totalPrice()"

method="post">

<div class="table-content table-responsive">

<table class="myTable">

<thead>

<tr>

<th class="indecor-product-remove">remove</th>

<th class="indecor-product-thumbnail">images</th>

<th class="cart-product-name">Product</th>

<th class="indecor-product-price">Unit Price</th>

<th class="indecor-product-quantity">Quantity</th>

<th class="indecor-product-subtotal">Total</th>

</tr>

</thead>

<tbody>

<c:forEach items="${sessionScope.cartList }" var="cl">

<tr>

<td class="indecor-product-remove"><a

href="${pageContext.request.contextPath}/DeleteCartServlet?productId=${cl.productId}"><i

class="fa fa-times"></i></a></td>

<td class="indecor-product-thumbnail"><a href="#"><img

src="${cl.productPicture }" width="100px" height="100px"></a></td>

<td class="indecor-product-name"><a href="#">${cl.productName}</a></td>

<td class="indecor-product-price"><span class="amount">$${cl.productPrice}</span></td>

<td class="indecor-product-quantity">

<span>${cl.productAmount }</span>

<!-- <input value="1" name="Cartquantity" class="Cartquantity" type="text"> -->

<a class="view"

href="${pageContext.request.contextPath}/UpdateAmountJumpServlet?productId=${cl.productId}">修改数量</a></td>

<td class="product-subtotal" onsubmit="return money()"><span

id="TotalPrice" class="TotalPrice">${cl.productPrice*cl.productAmount }</span></td>

</tr>

</c:forEach>

</tbody>

</table>

</div>

<div class="row">

<div class="col-12">

<div class="coupon-all">

<div class="coupon">

<input id="coupon_code" class="input-text" name="coupon_code"

value="" placeholder="Coupon code" type="text"> <input

class="button" name="apply_coupon" value="Apply coupon"

type="submit">

</div>

<div class="coupon2">

<input class="button" name="update_cart" value="Update cart"

type="submit">

</div>

</div>

</div>

</div>

<div class="row">

<div class="col-md-5 ml-auto">

<div class="cart-page-total">

<h2>Cart totals</h2>

<ul>

<li>Total <span>$130.00</span></li>

</ul>

<!-- bbutton最好用class -->

<button class="updateCart" type="button">Update Price</button>

<!-- <button id="updateCart" type="button">Update Price</button> -->

<a href="#">Proceed to checkout</a>

</div>

</div>

</div>

</form>

下面是点击Update Price后的代码:

<script type="text/javascript">

$(".updateCart").click(function(){

alert("一点击");

alert($(".myTable tr").eq(1).find("td:eq[6]").val());

// alert($(".myTable").rows.length);

var sum = 0;

for (var i = 1; i <= $(".myTable").find("tr").length; i++) {

sum += parseFloat($(".myTable").find("tr:eq[i]").find("td:eq[6]").innerText)

}

alert(sum);

});

</script>