Javascript: if an array has object or is no empty

Question

I have some JSON data like below:

{
  "errorCode": null,
  "message": "Success",
  "result": {

  },
  "totalRecord": 0,
  "checkAccess": true,
  "token": "fb8904acf4dbf0406ac3fd16acd9b84807d2a0e2913aecc3f39e90ca4b53161af6058ca5ee46b9877b75292e5ca9b8df969a325fa3b40c0e4acde546a431f55f6c07de8a854b9e0bf6aeba314d239267"
}

In the JSON you can find the "result" is empty, but how can I identify it by if statement? I tried to use !== "undedined" and !==null but the statment still executes.

if(trend1_data[0].result !== 'undefined'){
    var resultone = trend1_data[0].result;
    var chartVal1 = resultone.mention30d.chartValues;
    for(var i=0; i < chartVal1.length; i++){
        vol1.push(chartVal1[i].value);//a for loop to generate value array
        Xvol1.push(chartVal1[i].date);// for xaris values e.g:date
    }
}

You're checking if `resultone` exists before you're declaring it. Switch lines one and two of that second code block you have. — Cerbrus, May 09 '16 at 09:25

score 2 · Accepted Answer · answered May 09 '16 at 09:28

2

result is an object inside json array

Hope this will be useful

var a = [{
"errorCode": null,
  "message": "Success",
  "result": {

  },
  "totalRecord": 0,
  "checkAccess": true,
  "token": "someValue"
} 
]

alert(Object.keys(a[0].result).length)

jsfiddle

answered May 09 '16 at 09:28

brk

48,835
10
56
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I can't modify the JSON file so i am not able to put var obj in there – Anson Aştepta May 09 '16 at 09:39
i tried (trend2_data[0].result).length but the outcome is undefined – Anson Aştepta May 09 '16 at 09:40
Object.keys(trend2_data[0].result).length; seem fine – Anson Aştepta May 09 '16 at 09:41

score 0 · Answer 2 · answered May 09 '16 at 09:30

if the obj is

var obj = {
  "errorCode": null,
  "message": "Success",
  "result": {

  },
  "totalRecord": 0,
  "checkAccess": true,
  "token": "fb8904acf4dbf0406ac3fd16acd9b84807d2a0e2913aecc3f39e90ca4b53161af6058ca5ee46b9877b75292e5ca9b8df969a325fa3b40c0e4acde546a431f55f6c07de8a854b9e0bf6aeba314d239267"
}

try this

resultone = obj.result && ( Array.isArray( obj.result ) && obj.result.length ) || Object.keys(obj.result).length;

This will check obj.result in following order (second step is optional if you already know that result can only be an object not an array)

1) If obj.result exists

2) If yes, then whether it is an array and if it is an array then does it have items in it

3) If it is not an array, then does it have any keys.

resultone will be either true/false now, Now you can use it as

if ( resultone )
{
}

I can't modify the JSON file so i am not able to put var obj in there — Anson Aştepta, May 09 '16 at 09:35
@anson920520 thats fine, I have just shown it as an example here. — gurvinder372, May 09 '16 at 09:36

score -1 · Answer 3 · edited May 23 '17 at 10:28

-1

Your resultone is either undefined or you should check differently with resultone < array.length

Check How do I check if a JavaScript array value is empty or null?

edited May 23 '17 at 10:28

Community

1
1

answered May 09 '16 at 09:28

Loek

4,037
19
35

Javascript: if an array has object or is no empty

3 Answers3