Check if object key exists within object

Question

I\'m trying to take some data from an existing object and group it into a new one. The problem I am having is checking if the object key exists so I can either create a new

Answer 1

I have run into this pattern a lot, and what I end up doing is:

if (object[key]) {
    //exists
} else {
    // Does not exist
}

so I think in your case it will be:

if (groups[group_key]) {
    // Exists
} else {
    // Does not exist 
}