Javascript 检查对象数组中是否存在对象ID
我从sessionStorage解析了这个对象数组。我想在数组中添加一个项目,但如果它已经存在,则只更新项目的数量,不要再次添加。以下是我迄今为止所尝试的:Javascript 检查对象数组中是否存在对象ID,javascript,session-storage,Javascript,Session Storage,我从sessionStorage解析了这个对象数组。我想在数组中添加一个项目,但如果它已经存在,则只更新项目的数量,不要再次添加。以下是我迄今为止所尝试的: var tobeSaved = store.getters.printCart; //This is the data that I want to add if(tobeSaved.length){ if(sessionStorage.length){ var existingCart
var tobeSaved = store.getters.printCart; //This is the data that I want to add
if(tobeSaved.length){
if(sessionStorage.length){
var existingCart = JSON.parse(sessionStorage.cart); //This is the sessionStorage items
var size = Object.keys(existingCart).length;
const found = tobeSaved.some(el => el.itemID === existingCart.itemID);
if(found){
} else{
existingCart.push(tobeSaved[0]);
let myObj_serialized = JSON.stringify(existingCart);
sessionStorage.setItem('cart', myObj_serialized);
}
} else{
let myObj_serialized = JSON.stringify(tobeSaved);
sessionStorage.setItem('cart', myObj_serialized);
}
这是我的会话存储阵列:
0:
itemID: "11111"
itemName: "sessionItem1"
itemPrice: 550
itemQuantity: 1
1:
itemID: "22222"
itemName: "sessionItem2"
itemPrice: 550
itemQuantity: 1
这是我的tobeSaved对象:
itemID: "11111",
itemName: "sessionItem1"
itemPrice: 550
itemQuantity: 6
我想做的是,如果TobeSave已经存在于现有购物车中,它应该只更新数量,但如果它不存在,则在数组中添加另一个对象。这应该适用于您。
您正在项目上循环,理想情况下,您应该在现有数组上循环,并检查ID是否存在
const found = tobeSaved.some(el => el.itemID === existingCart.itemID);
应该是
const found = existingArray.some(el => el.itemID === toBeSaved.itemID);
或者就像我使用find一样,这对我来说似乎是个不错的选择
let obj = exisitngArr.find(o => o.ID === newObj.ID);
var arr=[{
itemID: "11111",
itemName: "sessionItem1",
itemPrice: 550,
itemQuantity: 1
},
{
itemID: "22222",
itemName: "sessionItem2",
itemPrice: 550,
itemQuantity: 1
}];
window.sessionStorage.setItem('cart',JSON.stringify(arr));
var exisitngArr = JSON.parse(window.sessionStorage.getItem('cart'));
var newObj = {itemID: "11111",
itemName: "sessionItem1",
itemPrice: 550,
itemQuantity: 6}
function updateData(){
let obj = exisitngArr.find(o => o.ID === newObj.ID);
if(obj!== undefined && obj !== null){
obj.itemQuantity = newObj.itemQuantity;
} else {
exisitngArr.push(newObj);
}
window.sessionStorage.setItem('cart',JSON.stringify(exisitngArr));
}
updateData();
console.log(JSON.parse(window.sessionStorage.getItem('cart')));
或者这个怎么样
const SessionStorage = [
{
itemID: "11111",
itemName: "sessionItem1",
itemPrice: 550,
itemQuantity: 1,
},
{
itemID: "22222",
itemName: "sessionItem2",
itemPrice: 550,
itemQuantity: 1,
}
];
const toBeSaved = {
itemID: "11111",
itemName: "sessionItem1",
itemPrice: 550,
itemQuantity: 6,
}
const addOrUpdate = (SessionStorageArray, toBeSavedObject) => {
const index = SessionStorageArray.findIndex(session => session.itemID === toBeSavedObject.itemID);
if (index === -1) {
SessionStorageArray.push(toBeSavedObject);
} else {
SessionStorageArray[index].itemQuantity = toBeSavedObject.itemQuantity;
}
return SessionStorageArray;
};
console.table(addOrUpdate(SessionStorage, toBeSaved));
有些(…)使用
existingCart.find(…)
从数组中获取现有元素的值。如果.find()
的结果不是未定义的
更新数量。