如何在对象中设置值

Question

我必须在对象中设置值。

这是问题所在：当我尝试在具有某些道具的对象中编写道具时，以前的道具将被删除。

我解决了两个案例，这是最后一个。我需要保存 test2。我该如何解决？

谢谢。

var obj = {
  keyOne: "foo",
  keyTwo: {
    test1: "baz",
    test2: {
      test21: ["bar"],
    }
  }
}

function setObjectProperty(obj, string, value) {
  var path = string.split('.');
  var currentObj = obj;
  for (var i = 0; i < path.length - 1; i++) {
    if (!currentObj[path[i]] || currentObj[path[i]] != "string") {
      currentObj[path[i]] = {};
      currentObj = currentObj[path[i]];
    }
  }
  currentObj[path[path.length - 1]] = value;
};

setObjectProperty(obj, 'keyOne', 'new');
setObjectProperty(obj, 'keyOne.key.key2', 'newnew');
setObjectProperty(obj, 'keyTwo.test1', 'zzz');

console.log(obj);

Answer 1

测试 currentObj[path[i]] != "string" 看起来很奇怪，我想你想用 typeof 代替。

在你的循环中，你应该在每一步都前进，但只创建一个不存在的对象。

工作代码：

function setObjectProperty(obj, string, value) {
  var path = string.split('.');
  var currentObj = obj;
  for (var i = 0; i < path.length - 1; i++) {
    if (!currentObj[path[i]] || typeof currentObj[path[i]] == "string") {
      currentObj[path[i]] = {};
    }
    currentObj = currentObj[path[i]];
  }
  currentObj[path[path.length - 1]] = value;
};

Answer 2

进行了少量更正。

无论创建子对象都需要推进对象路径
检查字符串类型，需要使用typeof

var obj = {
  keyOne: "foo",
  keyTwo: {
    test1: "baz",
    test2: {
      test21: ["bar"],
    }
  }
}

function setObjectProperty(obj, string, value) {

  var path = string.split('.');
  var currentObj = obj;
  
  for (var i = 0; i < path.length - 1; i++) {
    if (!currentObj[path[i]] || typeof currentObj[path[i]] === 'string') {
      currentObj[path[i]] = {};     
    }
    
     currentObj = currentObj[path[i]];
  }
  currentObj[path[path.length - 1]] = value;
};

setObjectProperty(obj, 'keyOne', 'new');
setObjectProperty(obj, 'keyOne.key.key2', 'newnew');
setObjectProperty(obj, 'keyTwo.test1', 'zzz');

console.log(obj);

Answer 3

这是您要找的吗？

const store = {
  keyOne: "foo",
  keyTwo: {
    test1: "baz",
    test2: {
      test21: ["bar"],
    }
  }
}

function getKeys(key) {
  return key.split(".").filter(k => k.length);
}

function assignProps(object, keys, value = null, root = null) {
  root = root || object;
  
  const key = keys.shift();

  if (!key) return root;

  object[key] = keys.length === 0 ? value : {};

  assignProps(object[key], keys, value, root);
}

assignProps(store, getKeys("keyOne.foo.bar"), "baz");
assignProps(store, getKeys("keyTwo.test1.test2"), "value");

console.log(store);

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