How to check if a key exists in Json Object and get its value

Question

Let say this is my JSON Object

{
  "LabelData": {
    "slogan": "AWAKEN YOUR SENSES",
    "jobsearch": "JOB SEARCH",
    "contact": "CONTACT",
    "video": "ENCHANTING BEACHSCAPES",
    "createprofile": "CREATE PROFILE"
  }
}

I need to know that either 'video` exists or not in this Object, and if it exists i need to get the value of this key. I have tried following, but i am unable to get value of this key.

 containerObject= new JSONObject(container);
 if(containerObject.hasKey("video")){
  //get Value of video
}

why dont you use gson library for parsing Json to Java Obj and vise versa — Vikas Tiwari, Apr 11 '17 at 09:26
container is simple JsonObject. I am using simple JSONObject in android — dev90, Apr 11 '17 at 09:27

score 60 · Accepted Answer · edited Apr 10 '19 at 08:40

60

Use below code to find key is exist or not in JsonObject. has("key") method is used to find keys in JsonObject.

containerObject = new JSONObject(container);
//has method
if (containerObject.has("video")) {
    //get Value of video
    String video = containerObject.optString("video");
}

If you are using optString("key") method to get String value then don't worry about keys are existing or not in the JsonObject.

edited Apr 10 '19 at 08:40

Nicholas K

15,148
7
31
57

answered Apr 11 '17 at 09:27

Chetan Joshi

5,582
4
30
43

Note that you can check only root keys with has(). Get values with get(). – Zon May 23 '17 at 11:57
if you dont find the containerObject.has you can try containerObject.containsKey.. I did this.. – Vijay Jul 11 '20 at 20:32

score 11 · Answer 2 · edited Apr 10 '19 at 08:38

11

Use:

if (containerObject.has("video")) {
    //get value of video
}

edited Apr 10 '19 at 08:38

Nicholas K

15,148
7
31
57

answered Apr 11 '17 at 09:26

TysonSubba

1,362
2
12
16

score 5 · Answer 3 · edited Apr 10 '19 at 08:39

5

containerObject = new JSONObject(container);
if (containerObject.has("video")) { 
   //get Value of video
}

edited Apr 10 '19 at 08:39

Nicholas K

15,148
7
31
57

answered Apr 11 '17 at 09:28

Mukeshkumar S

785
1
14
30

score 5 · Answer 4 · answered Apr 11 '17 at 09:29

From the structure of your source Object, I would try:

containerObject= new JSONObject(container);
 if(containerObject.has("LabelData")){
  JSONObject innerObject = containerObject.getJSONObject("LabelData");
     if(innerObject.has("video")){
        //Do with video
    }
}

score 5 · Answer 5 · edited Apr 13 '17 at 12:38

Please try this one..

JSONObject jsonObject= null;
try {
     jsonObject = new JSONObject("result........");
     String labelDataString=jsonObject.getString("LabelData");
     JSONObject labelDataJson= null;
     labelDataJson= new JSONObject(labelDataString);
     if(labelDataJson.has("video")&&labelDataJson.getString("video")!=null){
       String video=labelDataJson.getString("video");
     }
    } catch (JSONException e) {
      e.printStackTrace();
 }

score 4 · Answer 6 · answered Apr 11 '17 at 09:41

Try

private boolean hasKey(JSONObject jsonObject, String key) {
    return jsonObject != null && jsonObject.has(key);
}

  try {
        JSONObject jsonObject = new JSONObject(yourJson);
        if (hasKey(jsonObject, "labelData")) {
            JSONObject labelDataJson = jsonObject.getJSONObject("LabelData");
            if (hasKey(labelDataJson, "video")) {
                String video = labelDataJson.getString("video");
            }
        }
    } catch (JSONException e) {

    }

does this work for lists and nested lists in a json? – chocokoala Aug 01 '23 at 14:14 — chocokoala, Aug 01 '23 at 14:14

score 4 · Answer 7 · answered Apr 11 '17 at 09:43

4

JSONObject class has a method named "has". Returns true if this object has a mapping for name. The mapping may be NULL. http://developer.android.com/reference/org/json/JSONObject.html#has(java.lang.String)

answered Apr 11 '17 at 09:43

Fathima km

2,539
3
18
26

Rizwan · Answer 8 · 2017-04-11T09:46:34.110

1

JSONObject root= new JSONObject();
JSONObject container= root.getJSONObject("LabelData");

try{
//if key will not be available put it in the try catch block your program 
 will work without error 
String Video=container.getString("video");
}
catch(JsonException e){

 if key will not be there then this block will execute

 } 
 if(video!=null || !video.isEmpty){
  //get Value of video
}else{
  //other vise leave it
 }

i think this might help you

edited Apr 11 '17 at 09:46

answered Apr 11 '17 at 09:35

Rizwan

163
2
8

if key is not exist then your if conditions executes or not ? – Chetan Joshi Apr 11 '17 at 09:36
1

Using Exception handling for such thing is very bad solution. – Selvin Apr 11 '17 at 10:05

How to check if a key exists in Json Object and get its value

8 Answers8

Linked