Get key from value in Json

Question

I have a Json object in following format

MyJsonObject= {
    'Animal': ['Lion', 'Tiger', 'Elephant'],
    'Human': ['Man', 'Woman']
};

I want to get the key as return type if we pass value to function. Eg If I pass value =Man, function should return Human as return type. similarly, If I passed Tiger as value than I want to get Animal as return value.

Any help will be appreciated

score 1 · Answer 1 · answered Jul 21 '15 at 18:25

1

Hi the snippet bellow should work.

You can try here http://jsfiddle.net/xtdqodzk/1/

MyJsonObject= {
    'Animal': ['Lion', 'Tiger', 'Elephant'],
    'Human': ['Man', 'Woman']
};
function find(value){
    for(var prop in MyJsonObject ){
        if(MyJsonObject.hasOwnProperty(prop)){
            for(var i =0 ;i<MyJsonObject[prop].length;i++){
                if(MyJsonObject[prop][i] === value){
                    return prop;
                }
             }
        }
    }
}
alert(find('Man'));

answered Jul 21 '15 at 18:25

Su4p

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Thanks ... it worked for me. Appreciate your help – LilRazi Jul 21 '15 at 19:02
@JNil if it's working, it would be nice to accept my answer so you can get some points and I too. – Su4p Jul 22 '15 at 12:36

score 1 · Answer 2 · answered Jul 21 '15 at 18:45

You can try to modify Object prototype

Object.prototype.findKey = function(value) {
  for (var key in this) {
    if (this.hasOwnProperty(key)) {
      for (var i = 0; i < this[key].length; i++) {
        if (this[key][i] === value) {
          return key;
        }
      }
    }
  }
}

var MyJsonObject = {
    'Animal': ['Lion', 'Tiger', 'Elephant'],
    'Human': ['Man', 'Woman']
};

console.log(MyJsonObject.findKey('Man'));

The advantage of doing this way is if you have another json object you can call .findKey function on that object as well since all objects inherit functions and properties from Object.prototype object (prototypal inheritance).

Get key from value in Json

2 Answers2