Question

I have a real time feed of names entering a JS function and I would like to create an object such as:

var renderObj= {
{"name": "test1", "size": 3938},
{"name": "test2", "size": 3812},
{"name": "test3", "size": 6714}
};

So renderObj is empty to start. Each time a name comes in, I need to check if it exists in the object. If it does, update the size.

Can anyone advise?

Answer 1

You can’t have unnamed items in an object. Use an array instead:

var renderObj = [
  {"name": "test1", "size": 3938},
  {"name": "test2", "size": 3812},
  {"name": "test3", "size": 6714}
];

Loop through the array to check if a name exists:

var index = -1;
for (var i = 0; i < renderObj.Length; i++) {
  if (renderObj[i].name == name) {
    index = i;
    break;
  }
}

Now check the result. I assume that you want to add an object if the name doesn’t exist yet. You didn’t say how you wanted the size updated, so I assumed that you wanted to add the new value to the previous:

if (index == -1) {
  renderObj.push({ name: name, size: size });
} else {
  renderObj[index].size += size;
}