从对象拼接属性？

Question

Is there a utility (jquery, lodash, etc) that extracts properties from an object to another object and then deletes them from the original object? Similar to Array's splice?

obj1 = {color:"red", age:"23", name:"cindy"}
obj2 = extract(obj1, ["color","name"])

result:

obj1 is { age:23 }
obj2 is {color:"red", name:"cindy"}

Answer 1

You could use a function for it, which iterates the keys and returns a new objectc and deletes the keys from the source object.

 function extract(object, keys) { return keys.reduce(function (o, k) { o[k] = object[k]; delete object[k]; return o; }, {}); } var obj1 = { color: "red", age: "23", name:"cindy" }, obj2 = extract(obj1, ["color","name"]); console.log(obj1); console.log(obj2); 

Answer 2

An alternative way is to use underscore's _.object() method to create a quick custom extract fn:

function extract(properties, object) {
  return _.object(properties, properties.map(prop => object[prop]));
}

DEMO

Answer 3

Here's how custom extract function may be defined:

 function extract(o, keys) { var newObj = {}; keys.forEach(function(k){ if (o.hasOwnProperty(k)) { // check if a key exists in `source` object newObj[k] = o[k]; delete o[k]; // removing property from `source` object } }); return newObj; } var obj1 = {color:"red", age:"23", name:"cindy"}, obj2 = extract(obj1, ["color","name"]); console.log(obj1); console.log(obj2);