Merge javascript objects in array with same key

Question

What is the best way to reorganize array into output? I need to merge all value keys (whether array or not) into objects sharing the same name key. There is something similar here, but that doesn't answer my question because I have arrays as well.

var array = [
    {
        name: "foo1",
        value: "val1"
    }, {
        name: "foo1",
        value: [
            "val2",
            "val3"
        ]
    }, {
        name: "foo2",
        value: "val4"
    }
];

var output = [
    {
        name: "foo1",
        value: [
            "val1",
            "val2",
            "val3"
        ]
    }, {
        name: "foo2",
        value: [
            "val4"
        ]
    }
];

Yes, I can write endless for loops and several arrays in between, but is there a simple(r) shortcut? Thanks!

question from:https://stackoverflow.com/questions/33850412/merge-javascript-objects-in-array-with-same-key

Answer 1

Here is one option:-

var array = [{
  name: "foo1",
  value: "val1"
}, {
  name: "foo1",
  value: ["val2", "val3"]
}, {
  name: "foo2",
  value: "val4"
}];

var output = [];

array.forEach(function(item) {
  var existing = output.filter(function(v, i) {
    return v.name == item.name;
  });
  if (existing.length) {
    var existingIndex = output.indexOf(existing[0]);
    output[existingIndex].value = output[existingIndex].value.concat(item.value);
  } else {
    if (typeof item.value == 'string')
      item.value = [item.value];
    output.push(item);
  }
});

console.dir(output);