1. 对象的遍历 我们可以使用for...in循环或Object.keys()、Object.values()、Object.entries()等方法来遍历对象。 示例代码: constobj={name:'Alice',age:30,city:'New York'};// 使用 for...in 循环遍历for(letkeyinobj){if(obj.hasOwnProperty(key)){console.log(`Key:${key}, Value:${obj[key...
Object.entries()很强大,它返回对象的键和属性值,而且它们是成对的,比如:[ [key1, value1], [key2, value2], ..., [keyN, valueN] ]。 可能直接使用有些不爽。幸运的是,数组在for...of循环中传入let [x, y] = array,很容易得到对应的访问键和值 letperson = {run:'i run',eat:'i eat',...
function iterateNestedObject(obj, indent = 0) { for (let key in obj) { if (obj.hasOwnProperty(key)) { let value = obj[key]; if (typeof value === 'object') { console.log(`${' '.repeat(indent)}${key}:`); iterateNestedObject(value, indent + 2); } else { console.log...
// iterate through key-value gracefully const obj = { a: 5, b: 7, c: 9 }; for (const [key, value] of Object.entries(obj)) { console.log(`${key} ${value}`); // "a 5", "b 7", "c 9" } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17...
To rename object keys in JavaScript here are the different approaches you may use: Solution 1: Using simple assignment If you want torename an object key in JavaScript, you can achieve it by assigning the value of the existing key to a new property with the desired key, and subsequently re...
Object.defineProperty(obj,'newDataProperty',{ value:101, writable:true, enumerable:true, configurable:true}) obj.newDataProperty= 88console.log(obj.newDataProperty)//88 5、Object.is 函数 (JavaScript)。返回一个值,该值指示两个值是否相同。语法:Object.is(value1, value2) ...
function deepIterateKeys(obj) { for (let key in obj) { console.log(key); // 打印当前键 if (typeof obj[key] === 'object') { deepIterateKeys(obj[key]); // 递归遍历嵌套对象的键 } } } const obj = { key1: 'value1',
letuser={name:"John",age:30};// loop over keys-and-valuesfor(let[key,value]ofObject.entries(user)){alert(`${key}:${value}`);// name:John, then age:30} 对于Map 的遍历代码类似,它更简单一些,因为它是可迭代的: letuser=newMap();user.set("name","John");user.set("age","30")...
1、返回数组,格式为 key: value 2、结果数组不要求顺序 1. for in for-in会漏掉不可枚举属性; for-in会遍历原型链上的属性,需要配合hasOwnProperty过滤 functioniterate(obj){// hasOwnProperty// 如果使用for in遍历,很重要的一点是不能遍历的自身属性会被遗漏varresult=[];for(varpinobj){if(obj.hasOwn...
function*iterateObjectValues(collection){for(letkeyofObject.keys(collection)){yieldcollection[key];}}//生成给定数组中每个项的生成器。function*iterateArrayElements(collection){for(letelementofcollection){yieldelement;}} 这些函数简洁小巧,易于使用。麻烦的是这些函数中的每一个都会对传入的集合做出判断。它是...