下面的代码来自jQuery UI自动完成:
var projects = [
{
value: "jquery",
label: "jQuery",
desc: "the write less, do more, JavaScript library",
icon: "jquery_32x32.png"
},
{
value: "jquery-ui",
label: "jQuery UI",
desc: "the official user interface library for jQuery",
icon: "jqueryui_32x32.png"
},
{
value: "sizzlejs",
label: "Sizzle JS",
desc: "a pure-JavaScript CSS selector engine",
icon: "sizzlejs_32x32.png"
}
];
例如,我想更改jquery-ui的desc值。我该怎么做呢?
此外,是否有更快的方法来获取数据?我的意思是给对象一个名字来获取它的数据,就像数组中的对象一样?比如jquery-ui。jquery-ui。desc = ....
根据以下数据,我们想用西瓜替换summerFruits列表中的浆果。
const summerFruits = [
{id:1,name:'apple'},
{id:2, name:'orange'},
{id:3, name: 'berries'}];
const fruit = {id:3, name: 'watermelon'};
有两种方法。
第一种方法:
//create a copy of summer fruits.
const summerFruitsCopy = [...summerFruits];
//find index of item to be replaced
const targetIndex = summerFruits.findIndex(f=>f.id===3);
//replace the object with a new one.
summerFruitsCopy[targetIndex] = fruit;
第二种方法:使用map和spread:
const summerFruitsCopy = summerFruits.map(fruitItem =>
fruitItem .id === fruit.id ?
{...summerFruits, ...fruit} : fruitItem );
summerFruitsCopy列表现在将返回一个更新对象的数组。
ES6方式,不改变原始数据。
var projects = [
{
value: "jquery",
label: "jQuery",
desc: "the write less, do more, JavaScript library",
icon: "jquery_32x32.png"
},
{
value: "jquery-ui",
label: "jQuery UI",
desc: "the official user interface library for jQuery",
icon: "jqueryui_32x32.png"
}];
//find the index of object from array that you want to update
const objIndex = projects.findIndex(obj => obj.value === 'jquery-ui');
// Make sure to avoid incorrect replacement
// When specific item is not found
if (objIndex === -1) {
return;
}
// make new object of updated object.
const updatedObj = { ...projects[objIndex], desc: 'updated desc value'};
// make final new array of objects by combining updated object.
const updatedProjects = [
...projects.slice(0, objIndex),
updatedObj,
...projects.slice(objIndex + 1),
];
console.log("original data=", projects);
console.log("updated data=", updatedProjects);