Parse the JSON data in javascript

Question

I Have following JSON data, I need to iterate this data based on Keytype in JAVASCRIPT. It should return record from only the passed key code. Say i need record from 438 means it should give me only following data. (ex:"K": "43800001", "D": "Data1")

{
 "GroupCode": {
 "PickType": [
 {
 "@KeyType": "438",
 "R": [
 {
 "K": "43800001",
 "D": "Data1"
 }
 ]
 },
 {
 "@KeyType": "439",
 "R": [
 {
 "K": "43900001",
 "D": "Data2"
 }
 ]
 },
 {
 "@KeyType": "440",
 "R": [
 {
 "K": "44000001",
 "D": "Data3"
 }
 ]
 },
 {
 "@KeyType": "441",
 "R": [
 {
 "K": "44100001",
 "D": "Data4"
 }
 ]
 }
 ]
 }
}

as I'm not good in java script and new to it, i haven't tried coding for this. Please help me in getting the data.

• Jaromanda X: JSON.parse parses JSON
• Parth Trivedi: you should try, not put it directly
• A. Wolff: @JaromandaX Why would he needs to parse it? It is already js object in valid JSON format
• Jaromanda X: I assumed from the question TITLE - my bad
• A. Wolff: @JaromandaX Oh ya, then it would be the answer ;)

Answer 1

Let us say the above is stored in a variable obj. You can get the result via following

var result = obj.GroupCode.PickType.filter(function(item){
 return item["@KeyType"] === "438"
 }).map(function(item){
 return item.R[0];
 });

Please note, result is an array. If you have unique object against the condition then for that you will have to check the length of array and then extract the object i.e. result[0] or result.shift()

• A. Wolff: Very close but returns an array. OP wants .map(...)[0]
• Nikhil Aggarwal: @A.Wolff - I was editing the answer with comments. Thank you
• A. Wolff: That's said, you don't need to map it: obj.GroupCode.PickType.filter(function(item){ return item["@KeyType"] === "438" })[0].R[0]; But somehow, your code is more readable
• Nikhil Aggarwal: @A.Wolff - I wish that was an answer so that I can upvote it :)
• ViKu: @nikil What is the purpose of item in filter function here

Answer 2

Working Fiddle here

function getByKeyType(keytype) {
 for(i in f.GroupCode.PickType) {
 if(f.GroupCode.PickType[i].KeyType == keytype) {
 return f.GroupCode.PickType[i].R[0];
 }
 }
 return null;
}
alert(getByKeyType(438).K)
alert(getByKeyType(438).D)

Answer 3

Try this

 function getByKeyType(keytype) {
 for(i in f.GroupCode.PickType) {
 if(f.GroupCode.PickType[i].KeyType == keytype) {
 return f.GroupCode.PickType[i].R[0];
 }
 }
 return null;
}

• A. Wolff: No, it won't work. var result = JSON.parse(obj); I think obj in OP's code is already an object

Answer 4

Try a simple jquery each loop and a if:

jquery:

$.each(obj.GroupCode.PickType,function(i,v){
 if (v["@KeyType"] == 438) {
 console.log(v.R)//v.R[0];
 }
});

javascript:

for(v in obj.GroupCode.PickType) {
 if (v["@KeyType"] == 438) {
 console.log(v.R)//v.R[0];
 }
}

• Sabaz: warning here, $.each is not a vanilla javascript , it comes with jQuery: a js lib. do not take it for granted knowledge. also op said he's new in javascript so maybe he'll get an error while testing your code and wondering "..why?", add some additional info
• Sabaz: eveything is possible, thank you for the edit and for the burning reply