Json Find in Javascript

Question

Is there a better way other than looping to find data in JSON? It's for edit and delete.

for(var k in objJsonResp) {
  if (objJsonResp[k].txtId == id) {
    if (action == 'delete') {
      objJsonResp.splice(k,1);
    } else {
      objJsonResp[k] = newVal;
    }
    break;
  }
}

The data is arranged as list of maps. Like:

[
  {id:value, pId:value, cId:value,...},
  {id:value, pId:value, cId:value,...},
  ...
]

Accepted Answer

(You're not searching through "JSON", you're searching through an array -- the JSON string has already been deserialized into an object graph, in this case an array.)

Some options:

Must Read

Use an Object Instead of an Array

If you're in control of the generation of this thing, does it have to be an array? Because if not, there's a much simpler way.

Say this is your original data:

[
    {"id": "one",   "pId": "foo1", "cId": "bar1"},
    {"id": "two",   "pId": "foo2", "cId": "bar2"},
    {"id": "three", "pId": "foo3", "cId": "bar3"}
]

Could you do the following instead?

{
    "one":   {"pId": "foo1", "cId": "bar1"},
    "two":   {"pId": "foo2", "cId": "bar2"},
    "three": {"pId": "foo3", "cId": "bar3"}
}

Then finding the relevant entry by ID is trivial:

id = "one"; // Or whatever
var entry = objJsonResp[id];

...as is updating it:

objJsonResp[id] = /* New value */;

...and removing it:

delete objJsonResp[id];

This takes advantage of the fact that in JavaScript, you can index into an object using a property name as a string -- and that string can be a literal, or it can come from a variable as with id above.

Json Find in Javascript

7 Answers

Must Read

Use an Object Instead of an Array

Chloe Bennett