根据另一个对象创建一个新的 javascript 对象
2020-06-25
75
我正在尝试创建一个新的 javascript 对象，该对象将具有基于另一个对象的新键名。我快完成了，但我的代码在行
// 失败此处
处失败，并出现
Uncaught TypeError: Cannot set property 'name' of undefined
。有什么想法可以解决此问题吗？此外，在这种情况下是否有更有效的方法来构建新对象？我需要它在较旧的 IE 浏览器上运行，因此采用这种方法。
originalObj = {"name":"John","age":30,"state":"CA","country":"USA"};
objCodes = {"name":101,"age":102,"state":103,"country":104};
// newObj = {101:"John", 102:30,103:"CA",104:"USA"};
newObj = {};
for (var i in originalObj) {
if (objCodes.hasOwnProperty(i)) {
// console.log(i, originalObj[i]);
console.log(objCodes[i],originalObj[i])
newObj.objCodes[i] = originalObj[i] // fails here
}
}
console.log(newObj); 3个回答
只需更改以下代码片段中的行
originalObj = {"name":"John","age":30,"state":"CA","country":"USA"};
objCodes = {"name":101,"age":102,"state":103,"country":104};
// newObj = {101:"John", 102:30,103:"CA",104:"USA"};
newObj = {};
for (var i in originalObj) {
if (objCodes.hasOwnProperty(i)) {
// console.log(i, originalObj[i]);
console.log(objCodes[i],originalObj[i])
newObj[objCodes[i]] = originalObj[i] // fails here
}
}
console.log(newObj);RacoonOnMoon
2020-06-25
originalObj = {"name":"John","age":30,"state":"CA","country":"USA"};
objCodes = {"name":101,"age":102,"state":103,"country":104};
// newObj = {101:"John", 102:30,103:"CA",104:"USA"};
newObj = {};
for (var i in originalObj) {
if (objCodes.hasOwnProperty(i)) {
// console.log(i, originalObj[i]);
console.log(objCodes[i],originalObj[i])
newObj[objCodes[i]] = originalObj[i] // fails here
}
}
console.log(newObj);
将点符号改为括号符号。
原因是 JavaScript 只允许使用点符号的有效名称，而这些名称不能以数字开头。在您的情况下，键设置为 101,102...等等，这是无效的。
编辑：动态属性名称只能通过括号符号使用，例如在您的情况下使用变量设置属性名称。
Shreyash bhatt
2020-06-25
您可以获取密钥，迭代它们并复制项目，如下所示：
originalObj = {"name":"John","age":30,"state":"CA","country":"USA"};
objCodes = {"name":101,"age":102,"state":103,"country":104};
// newObj = {101:"John", 102:30,103:"CA",104:"USA"};
newObj = {};
Object.keys(objCodes).forEach(i => newObj[objCodes[i]] = originalObj[i]);
Lajos Arpad
2020-06-25