javascript从已解析的对象调用Json Parse

Question

I have a Javascript class in ES6, and I want to write a LoadFromJson method.

the problem is that JSON.parse return an object and I cannot write :

//MyObject.loadFromJson method
loadFromJson(JsonString)
 {
   this=JSON.parse(jsonString); //INVALID//
 }

How can I achieve this from within my class. I know I could write :

myObject = JSON.parse(jsonString);

but that's not what I want, I need :

myObject = new MyObjectClass();
myObject.loadFromJson(JsonString);

I want to implement an "undo mechanism" in my object and to be able to save / restore the object.

Answer 1

You can't assign to this . Here is an example that copies all the attributes from the parsed object.

class MyObjectClass {
  loadFromJSON(jsonString) {
    const parsed = JSON.parse(jsonString);
    for (const key in parsed) this[key] = parsed[key];
  }
}

const myObject = new MyObjectClass();
myObject.loadFromJSON('{"a":2,"b":null,"c":"abc"}');
console.log(myObject);