Angular 2如何防止特定变量的数据绑定

Question

So I need to prevent data binding for a specific variable. I want to do it like this:

// data is mostly an object in my case.
// it would be nice if there's a global solution
function(data) {
    d = data; // variable that changes on user input
    oldD = data; // variable that shouldn't change on user input
}

but whenever I implement code like this the oldD variable will change when the d variable gets changed. And I would like to prevent this from happening. But how do I prevent such a thing?

Answer 1

You need to assign value without assigning reference of old object.

Here's solution for JavaScript/Angular.

let oldD = Object.assign({}, data);

Hope this helps.

Answer 2

Probably you are looking for, How to clone object.

function(data) {
    d = data; // variable that changes on user input  

    // creates brand new object with the same data
    let oldD = Object.create(data.constructor.prototype);
    data.constructor.apply(oldD);
}