Javascript Creating Array In Object And Push Data To The Array

I'm new to programming. I'm trying React and have function addComment which is executed when a user adds a comment to news.I need to create in this moment a property comments (arra

Solution 1:

Let's say you have an object like this.

   foo : {
       bar : "x"
    }

To create an array, simply initialize it to an empty array.

foo.newArray = []

If you console.log(foo), you will now see this

foo : {
   bar : "x",
   newArray : []
 }

This means your foo object has an empty array called newArray. You can add elements to it using the push() method.

Push a variable like this foo.newArray.push(myVariable); Push a string like this foo.newArray.push("myString"); Push an object like this

 foo.newArray.push({
    "bar2" : "val2"
 });

For more information on arrays check W3schools

In your particular case, just do ARTICLES.push({})

Solution 2:

assuming that data exist in component's state , then handler will look something like that

addComment(index, inputCommentValue){
    // copy array , for not mutate stateletARTICLES = [...this.state.ARTICLES];
    // check if comments not existif(!ARTICLES[index].comments) ARTICLES[index].comments=[];
    // add new comment to arrayARTICLES[index].comments.push(inputCommentValue);
    // update component with new articlesthis.setState({ARTICLES:ARTICLES});
}