Find the value of specific element satisfying condition from json array

Question

Friends I have following like json array

[
   {
      "Rate":100.0,
      "MaterialID":"BOLT",
      "BrandName":"",
      "Description":"",
      "Unit":"KG",
      "TokenNumber":2
   },
   {
      "Rate":null,
      "MaterialID":"PLYWOOD",
      "BrandName":"",
      "Description":"",
      "Unit":"FT",
      "TokenNumber":2
   },
   {
      "Rate":null,
      "MaterialID":"SCREW 1.5 INCH",
      "BrandName":"",
      "Description":"",
      "Unit":"KG",
      "TokenNumber":2
   }
]

I want to know the shortest way to find an element that has materialID with value PLYWOOD.
I can do it using for loop. But I want to know some shortcut for this something like

var unit = jsonArray[<whiere materialID == 'PLYWOOD']['Unit'];

You can use jQuery if required.

maybe this can help you http://stackoverflow.com/questions/777455/is-there-a-query-language-for-json — Ankur, Sep 01 '12 at 17:10
This is not JSON... it seems you are working with an array of objects. — Felix Kling, Sep 01 '12 at 17:11
Yes, but is your question about JSON? It seems to be about finding elements in an array. — Felix Kling, Sep 01 '12 at 17:18
Please do `alert(typeof jsonArray)`. Does it say `string` or `object`? — some, Sep 01 '12 at 18:21
Then it is no longer JSON but a normal javascript object (in this case an array). And yes, it is a huge difference. — some, Sep 01 '12 at 19:24

score 5 · Accepted Answer · answered Sep 01 '12 at 17:15

5

You may use $.grep

http://api.jquery.com/jQuery.grep/

answered Sep 01 '12 at 17:15

closure

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score 2 · Answer 2 · answered Sep 01 '12 at 18:06

jQuery is not required, so you could do it like this:

function findItem(arr, key, value) {
    for (var i = 0; i < ARR.length; i++) {
       if (arr[i][key] === value) {
           return(i);
       }
    }
    return(-1);
}

var plywoodIndex = findItem(data, "MaterialID", "PLYWOOD");
if (plywoodIndex !== -1) {
    // do something with the plywoodIndex object here
}

score 1 · Answer 3 · answered Sep 01 '12 at 17:54

1

As Raghaw has suggested. I find the way to do my work. I designed following function that can return the object with specified materialID.

Assumptions: materials is the array

function getMaterialFromArray(materialID) {
    return $.grep(materials, function (n, i) {
        return(n.MaterialID == materialID);
    })[0];
}

answered Sep 01 '12 at 17:54

shashwat

7,851
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1

Thanks Shashwat. your answer helps me after 4 years – Ubiquitous Developers Feb 26 '17 at 08:12
@ubiquitous I am glad to hear that it helped you. – shashwat Feb 26 '17 at 11:31

Find the value of specific element satisfying condition from json array

3 Answers3