问题描述
这是源对象:
var originalObj = {
"key1": "value1","key2": "value2","nestedobj1" : {
"nestedKey1" : "nestedValue1","nestedKey2" : "nestedValue2"
},"nestedArr1" : [
{
"nestedKey3" : "nestedValue3","nestedKey4" : "nestedValue4"
},{
"nestedKey5" : "nestedValue5","nestedKey6" : "nestedValue6"
}
],"key3": "value3","key4": "value4"
}
基本上,我只需要复制非对象和非数组的键。
在此示例中,key1
,key2
,key3
和key4
这就是我所做的:
var modobject = {}
Object.keys(originalObj).forEach((child) => {
// copy non-objects and non-arrays
if (typeof originalObj[child] !== 'object' &&
!Array.isArray(modobject[child])) {
modobject[child] = originalObj[child]
}
})
// Change modobject and expect originalObj is updated to 'value3_modified' as well
modobject['key3'] = 'value3_modified'
console.log(originalObj['key3']) // Outputs 'value3' - Key3 value was not modified
console.log(modobject['key3']) // Outputs 'value3_modified'
但是问题是,当我更新modobject
时,其更改没有传播到originalObj
。我知道,这是因为我正在将其复制为值。
因此,我尝试顶部复制整个对象,然后删除不应该存在的对象(数组和对象键):
// copy the entire object
modobject = originalObj
Object.keys(modobject).forEach((child) => {
// Delete objects and arrays - these should not be in the new object
if (typeof modobject[child] === 'object' ||
Array.isArray(modobject[child])) {
delete modobject[child]
}
})
// Update modobject and expect originalObj updated to 'value3_modified' as well
modobject['key3'] = 'value3_modified'
console.log(modobject) // Outputs 'value3_modified'
console.log(originalObj) // // Outputs 'value3_modified' but object and array keys deleted in originalObj
但是,这一次,我的问题是,因为它是可变的,所以我在modobject
上删除的密钥也在originalObj
中删除了。
我如何实现我想要的:
- 将非对象键和非数组键从
originalObj
复制到modobject
,同时保持其可变性?
这是我的小提琴: https://jsfiddle.net/keechan/hbdj9mcs/11/
帮助!谢谢!
解决方法
对不起,我不知道您到底想要什么,但我假设您想克隆原始对象,并希望保留安全的原始对象并修改克隆的对象。
检查是否适合您。
let modObject = JSON.parse(JSON.stringify(originalObj))
现在使用modObject(克隆的)执行任何操作,原来的Obj不会受到影响。
Stack Overflow: What is the most efficient way to deep clone an object in JavaScript?