Remove variable value link

soup3ee 0
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public oldClient: Client = new Client(); 
public client: Client = new Client();
private clientId: string = "xxx";

this.userService.getClient(this.clientId).subscribe((data: Client) => {
    this.client = data;
    this.oldClient = data;
    this.client.name = "test";

    console.log(this.client.name) // Output : "test"
    console.log(this.oldClient.name) // Output : "test"
});

Why when im changing a property from my variable "client" this will impact "oldCLient" and how can I prevent this ? Thanks.

typescript javascript angular
2 Answers

Use the ...(spread syntax) to create the new object.

this.client = {...data}

If you just assign one object to another, you'll just have two variables pointing to the same object in memory, ie, editing one will change the original object.

userW94E0

You can create a clone of the data object to lose reference using

var a = Object.assign({}, b);

In your case

this.client = Object.assign({}, data);
this.oldClient = Object.assign({}, data);
Kelum Bandara0
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