recently I was learning ng2, but found a problem with array assignment. I just wanted to assign the value of list1 to list2, but they made an association.
Code:
export class AppComponent {
public list1 = [];
public list2 = [];
constructor() {
this.list1 = ["1","2"];
this.list2 = this.list1;
this.list1.push("3");
console.log(this.list2);
}
}output:
(3)["1", "2", "3"] this.list2 = this.list1;
this sentence is equivalent to
your house number is "list1", and now there is another house number called "list2", which eventually points to your house. I suggest you make up the knowledge of stack.
simple way:
this.list2.push(...list1);Previous: Can itchat add group friends in batches?
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