javascript - 如何从javascript返回多个值到jsp

Question

我正在尝试在

中显示多个水果名称

    <input type ="text" id="fruitsname" name="fruit/>       

点击“添加到购物车”按钮后，但下面的函数仅返回一个水果名称而不是多个水果名称，如何在单击“添加到购物车”按钮后返回多个水果名称

 document.getElementById('fruitsname').value= cartArray[i].name;
 //returning only one fruit name to home.jsp instead of multiple fruits 
 name, how can I return multiple fruits name from JS file 

--------------home.jsp----------

  <a href="#" data-name="Orange" data-price="5" class="add-to-cart btn 
 btn-primary">Add to cart</a> // Adding Orange after clicking on Add to cart
  <a href="#" data-name="Banana" data-price="5" class="add-to-cart btn btn- 
  primary">Add to cart</a> // Adding Banana after clicking on Add to cart


  <form name="billing" action="billing.jsp">           
  <input type="text" id="fruitsname"name="fruits"/> // returning 
  fruits name from JS file in function displayCart() written towards last of 
  JS file
  <input type="submit"/>
  </form> 

---------------------JS文件----------------

 var shoppingCart = (function() {
 // =============================
 // Private methods and properties
 // =============================
 cart = [];

// Constructor
function Item(name, price, count) {
 this.name = name;
 this.price = price;
 this.count = count;
 }

 // Save cart
 function saveCart() {
 sessionStorage.setItem('shoppingCart', JSON.stringify(cart));
  }

  // Load cart
  function loadCart() {
  cart = JSON.parse(sessionStorage.getItem('shoppingCart'));
  }
  if (sessionStorage.getItem("shoppingCart") != null) {
  loadCart();
  }



 // Public methods and properties

 var obj = {};

 // Add to cart

 obj.addItemToCart = function(name, price, count) {
 for(var item in cart) {
 if(cart[item].name === name) {
 cart[item].count ++;
 saveCart();
 return;
 }
 }
 var item = new Item(name, price, count);
 cart.push(item);
 saveCart();
}
 // Set count from item
obj.setCountForItem = function(name, count) {
for(var i in cart) {
 if (cart[i].name === name) {
cart[i].count = count;
break;
 }
 }
 };
  // Remove item from cart
  obj.removeItemFromCart = function(name) {
 for(var item in cart) {
 if(cart[item].name === name) {
  cart[item].count --;
  if(cart[item].count === 0) {
    cart.splice(item, 1);
  }
  break;
}
}
saveCart();
}

 // Remove all items from cart
obj.removeItemFromCartAll = function(name) {
for(var item in cart) {
if(cart[item].name === name) {
cart.splice(item, 1);
break;
}
}
saveCart();
}

// Clear cart
obj.clearCart = function() {
cart = [];
saveCart();
}

// Count cart 
obj.totalCount = function() {
var totalCount = 0;
for(var item in cart) {
totalCount += cart[item].count;
 }
return totalCount;
 }

// Total cart
obj.totalCart = function() {
var totalCart = 0;
for(var item in cart) {
totalCart += cart[item].price * cart[item].count;
 }

 document.getElementById('idofinput').value=Number(totalCart.toFixed(2)); 
 // Here I gave an input "IDOFINPUT" to call it in input type in form in 
  home.jsp

 return Number(totalCart.toFixed(2));
 }

 // List cart
 obj.listCart = function() {
 var cartCopy = [];
 for(i in cart) {
 item = cart[i];
 itemCopy = {};
 for(p in item) {
  itemCopy[p] = item[p];

 }
 itemCopy.total = Number(item.price * item.count).toFixed(2);
 cartCopy.push(itemCopy)
}
 return cartCopy;
 }

// cart : Array
// Item : Object/Class
// addItemToCart : Function
// removeItemFromCart : Function
// removeItemFromCartAll : Function
// clearCart : Function
// countCart : Function
// totalCart : Function
// listCart : Function
// saveCart : Function
// loadCart : Function
return obj;
})();


// *****************************************
// Triggers / Events
// ***************************************** 
// Add item
 $('.add-to-cart').click(function(event) {
 event.preventDefault();
 var name = $(this).data('name');
 var price = Number($(this).data('price'));
 shoppingCart.addItemToCart(name, price, 1);
 displayCart();
 });

 // Clear items
 $('.clear-cart').click(function() {
 shoppingCart.clearCart();
 displayCart();
  });


function displayCart() {
var cartArray = shoppingCart.listCart();
var output = "";
for(var i in cartArray) {
output += "<tr>"
+ "<td>" + cartArray[i].name + "</td>" 
+ "<td>(" + cartArray[i].price + ")</td>"
+ "<td><div class='input-group'><button class='minus-item input-group- 
addon btn btn-primary' data-name=" + cartArray[i].name + ">-</button>"
+ "<input type='number' class='item-count form-control' data-name='" + 
 cartArray[i].name + "' value='" + cartArray[i].count + "'>"
+ "<button class='plus-item btn btn-primary input-group-addon' data- 
name=" + cartArray[i].name + ">+</button></div></td>"
+ "<td><button class='delete-item btn btn-danger' data-name=" + 
cartArray[i].name + ">X</button></td>"
 + " = " + "<td>" + cartArray[i].total + "</td>" +  "</tr>";}

 document.getElementById('fruitsname').value= cartArray[i].name; //retuning 
  fruits name to home.jsp but returning only one fruit name instead of 
 multiple fruits name

 $('.show-cart').html(output);
 $('.total-cart').html(shoppingCart.totalCart());
 $('.total-count').html(shoppingCart.totalCount());
 }

 // Delete item button

 $('.show-cart').on("click", ".delete-item", function(event) {
 var name = $(this).data('name')
 shoppingCart.removeItemFromCartAll(name);  
  displayCart();
 })


 // -1
 $('.show-cart').on("click", ".minus-item", function(event) {
 var name = $(this).data('name')
 shoppingCart.removeItemFromCart(name);
 displayCart();
 })
  // +1
  $('.show-cart').on("click", ".plus-item", function(event) {
  var name = $(this).data('name')
  shoppingCart.addItemToCart(name);
  displayCart();
  })

 // Item count input
  $('.show-cart').on("change", ".item-count", function(event) {
  var name = $(this).data('name');
  var count = Number($(this).val());
  shoppingCart.setCountForItem(name, count);
  displayCart();
  });

 displayCart();

Answer 1

在 jsp 文件中使用 request.getParameterValues("fruits"); 来获取所有具有 name="fruits" 的输入元素的值