I want to sort a object in javascript. I have this json:

var unsorted = {
    "2014": [
        {
            "title": "Book",
            "value": 10
        },
        {
            "title": "Cheese",
            "value": 2
        }
    ],
    "2015": [
        {
            "title": "Movie",
            "value": 9
        }
    ],
     "2016": [
        {
            "title": "Slay",
            "value": 90
        },
        {
            "title": "Back",
            "value": 22
        }
    ],
    "selected_year": 2015
};

So I want to sort the jsons inside these years based on the value. I tried it with this:

var sorted = unsorted.items.sort(function(a, b) {return a.value - b.value});

alert.log(unsorted);
alert.log(sorted);

but the problem is that I have another field which is not json "selected_year": 2015 and it throat an error TypeError: Cannot read property 'sort' of undefined

I don't know how to do it? Here's my JSFIDDLE

UPDATE: I want to sort the arrays inside "years" so I get this:

var sorted = {
        "2014": [
            {
              "title": "Cheese",
              "value": 2

            },
            {
              "title": "Book",
              "value": 10
            }
        ],
        "2015": [
            {
                "title": "Movie",
                "value": 9
            }
        ],
         "2016": [
             {
                 "title": "Back",
                 "value": 22
             },
            {
                "title": "Slay",
                "value": 90
            }

        ],
        "selected_year": 2015
    };

for example inside "2014" after sorting I have:

"2014": [
        {
          "title": "Cheese",
          "value": 2

        },
        {
        "title": "Book",
        "value": 10
        }
    ]

I want to sort a object in javascript. I have this json:

var unsorted = {
    "2014": [
        {
            "title": "Book",
            "value": 10
        },
        {
            "title": "Cheese",
            "value": 2
        }
    ],
    "2015": [
        {
            "title": "Movie",
            "value": 9
        }
    ],
     "2016": [
        {
            "title": "Slay",
            "value": 90
        },
        {
            "title": "Back",
            "value": 22
        }
    ],
    "selected_year": 2015
};

So I want to sort the jsons inside these years based on the value. I tried it with this:

var sorted = unsorted.items.sort(function(a, b) {return a.value - b.value});

alert.log(unsorted);
alert.log(sorted);

but the problem is that I have another field which is not json "selected_year": 2015 and it throat an error TypeError: Cannot read property 'sort' of undefined

I don't know how to do it? Here's my JSFIDDLE

UPDATE: I want to sort the arrays inside "years" so I get this:

var sorted = {
        "2014": [
            {
              "title": "Cheese",
              "value": 2

            },
            {
              "title": "Book",
              "value": 10
            }
        ],
        "2015": [
            {
                "title": "Movie",
                "value": 9
            }
        ],
         "2016": [
             {
                 "title": "Back",
                 "value": 22
             },
            {
                "title": "Slay",
                "value": 90
            }

        ],
        "selected_year": 2015
    };

for example inside "2014" after sorting I have:

"2014": [
        {
          "title": "Cheese",
          "value": 2

        },
        {
        "title": "Book",
        "value": 10
        }
    ]

• javascript
• jquery
• json
• sorting

• 1 sort is Array's method, unsorted is a simple plain vanilla js object. – gurvinder372 Commented Dec 11, 2017 at 10:03
• Just to be clear about what you're trying to do, objects have no concept of "sorted". But the visual representation can be rearranged, if that's your goal. – Andrew Commented Dec 11, 2017 at 10:05
• sort() is an array method, your data is a dictionary. You might want to reconsider your data structure or write your own sorting function – mike_t Commented Dec 11, 2017 at 10:05
• which one would you like to sort? sort sorts in situ. – Nina Scholz Commented Dec 11, 2017 at 10:06
• 1 Strange!! that no one of the upvoted answers pointed to the real problem in your code!!! Actually there's no unsorted.items. :o – cнŝdk Commented Dec 11, 2017 at 10:39

5 Answers 5

You can sort only array properties:

var unsorted = {
    "2014": [
        {
            "title": "Book",
            "value": 10
        },
        {
            "title": "Cheese",
            "value": 2
        }
    ],
    "2015": [
        {
            "title": "Movie",
            "value": 9
        }
    ],
     "2016": [
        {
            "title": "Slay",
            "value": 90
        },
        {
            "title": "Back",
            "value": 22
        }
    ],
    "selected_year": 2015
};

var sorted = Object.assign({}, unsorted);  // Copy the unsorted object

Object.keys(sorted).forEach(key => {
  if (Array.isArray(sorted[key])) {
     sorted[key].sort((a, b) => a.value - b.value);
  }
})

console.log(sorted);

Only sort those values which are array. You can check for array using Array.isArray.

var unsorted = { 2014: [{ title: "Book", value: 10 }, { title: "Cheese", value: 2 }], 2015: [{ title: "Movie", value: 9 }], 2016: [{ title: "Slay", value: 90 }, { title: "Back", value: 22 }], selected_year: 2015 };

Object
  .keys(unsorted)
  .forEach(k => {
    if(Array.isArray(unsorted[k]))
      unsorted[k].sort((a,b) => a.value - b.value);
  });

console.log(unsorted);

.as-console-wrapper { max-height: 100% !important; top: 0; }

You could check if the property is an array and sort it as desired.

var object = { 2014: [{ title: "Book", value: 10 }, { title: "Cheese", value: 2 }], 2015: [{ title: "Movie", value: 9 }], 2016: [{ title: "Slay", value: 90 }, { title: "Back", value: 22 }], selected_year: 2015 };

Object.keys(object).forEach(function (k) {
    if (!Array.isArray(object[k])) {
        return;
    }
    object[k].sort(function (a, b) {
        return a.value - b.value;
    });
});

console.log(object);

.as-console-wrapper { max-height: 100% !important; top: 0; }

You are mixing array of object and object that why you are getting this error, for selected_yea

TypeError: Cannot read property 'sort' of undefined

Sort it like this

var unsorted = { 2014: [{ title: "Book", value: 10 }, { title: "Cheese", value: 2 }], 2015: [{ title: "Movie", value: 9 }], 2016: [{ title: "Slay", value: 90 }, { title: "Back", value: 22 }], selected_year: 2015 };
var newArr = [];
for(let i in unsorted){
  if(i !== 'selected_year'){
    unsorted[i] = unsorted[i].sort(function(a, b) {
      return a.value - b.value;
    });
  }
}
console.log(unsorted);

This solution is more faster than others.

Check Time taken of this : https://jsfiddle/q976tk4r/

Other solutions : https://jsfiddle/q976tk4r/1/ or https://jsfiddle/q976tk4r/2/

Problem:

Actually there's no such property unsorted.items in your JSON object, there are several keys for years which can be accessed using Object.keys(unsorted).

Solution:

So loop over these elements with a .map() and check if the element is an array with Array.isArray() return it sorted, otherwise just return the value:

var sorted = Object.keys(unsorted).map(function(k) {
  if (Array.isArray(unsorted[k])) {
    return {
      [k]: unsorted[k].sort(function(a, b) {
        return a.value - b.value
      })
    }
  } else {
    return {
      [k]: unsorted[k]
    };
  }
});

Demo:

var unsorted = {
  "2014": [{
      "title": "Book",
      "value": 10
    },
    {
      "title": "Cheese",
      "value": 2
    }
  ],
  "2015": [{
    "title": "Movie",
    "value": 9
  }],
  "2016": [{
      "title": "Slay",
      "value": 90
    },
    {
      "title": "Back",
      "value": 22
    }
  ],
  "selected_year": 2015
};

var sorted = Object.keys(unsorted).map(function(k) {
  if (Array.isArray(unsorted[k])) {
    return {
      [k]: unsorted[k].sort(function(a, b) {
        return a.value - b.value
      })
    }
  } else {
    return {
      [k]: unsorted[k]
    };
  }
});
console.log(sorted);