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JavaScript time comparison with arrays

I'm working on a project where I need to get all the vacant classrooms for the day and basically filter out the ones being in use.
I get all the data from the school's own API with JSON response body that looks like this:
{
"status": "success",
"reservations": [
{
"id": "18935",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:51",
"startDate": "2017-04-27T11:00:00",
"endDate": "2017-04-27T13:00:00",
"resources": [
{
"id": "50",
"type": "room",
"code": "A440.5",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A440.5"
},
{
"id": "2995",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "2267",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "20362",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:05:05",
"startDate": "2017-04-27T11:00:00",
"endDate": "2017-04-27T14:00:00",
"resources": [
{
"id": "51",
"type": "room",
"code": "A450.1",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A450.1"
},
{
"id": "2402",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "3064",
"type": "realization",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "20237",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:05:05",
"startDate": "2017-04-27T11:15:00",
"endDate": "2017-04-27T13:00:00",
"resources": [
{
"id": "45",
"type": "room",
"code": "A420.4",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A420.4"
},
{
"id": "2433",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "3058",
"type": "realization",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "20888",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:57",
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T16:00:00",
"resources": [
{
"id": "62",
"type": "room",
"code": "A520.5",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A520.5"
},
{
"id": "3092",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "2444",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "22586",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:48",
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T17:00:00",
"resources": [
{
"id": "52",
"type": "room",
"code": "A450.3",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A450.3"
},
{
"id": "3004",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "2294",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "525",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "18816",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:58",
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T16:00:00",
"resources": [
{
"id": "41",
"type": "room",
"code": "A340.1",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A340.1"
},
{
"id": "2989",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "795",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "599",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "20431",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:56",
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T16:00:00",
"resources": [
{
"id": "40",
"type": "room",
"code": "A320.7",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A320.7/8"
},
{
"id": "2416",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "2386",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "18588",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:49",
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T16:00:00",
"resources": [
{
"id": "25",
"type": "room",
"code": "A130.1",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A130.1"
},
{
"id": "26",
"type": "room",
"code": "A130.3",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A130.3"
},
{
"id": "2979",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "582",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "18940",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:53",
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T16:00:00",
"resources": [
{
"id": "2996",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "2267",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "2268",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "31",
"type": "room",
"code": "A210.2",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A210.2"
}
],
"description": ""
},
{
"id": "12041",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:04:53",
"startDate": "2017-04-27T14:15:00",
"endDate": "2017-04-27T17:00:00",
"resources": [
{
"id": "2510",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "775",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "23",
"type": "room",
"code": "A520.7",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A520.7"
}
],
"description": ""
},
{
"id": "24630",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:05:05",
"startDate": "2017-04-27T14:15:00",
"endDate": "2017-04-27T17:00:00",
"resources": [
{
"id": "3277",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "42",
"type": "room",
"code": "A340.2",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A340.2"
}
],
"description": ""
},
{
"id": "27205",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:05:07",
"startDate": "2017-04-27T14:15:00",
"endDate": "2017-04-27T17:00:00",
"resources": [
{
"id": "35",
"type": "room",
"code": "A240.2",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A240.2"
},
{
"id": "775",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "3384",
"type": "realization",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "25917",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:05:00",
"startDate": "2017-04-27T15:15:00",
"endDate": "2017-04-27T16:00:00",
"resources": [
{
"id": "36",
"type": "room",
"code": "A240.4",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A240.4"
},
{
"id": "593",
"type": "realization",
"code": "",
"name": ""
},
{
"id": "595",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
},
{
"id": "21932",
"subject": "subjectName",
"modifiedDate": "2017-04-27T06:05:06",
"startDate": "2017-04-27T16:00:00",
"endDate": "2017-04-27T18:00:00",
"resources": [
{
"id": "43",
"type": "room",
"code": "A350.1",
"parent": {
"id": "2",
"type": "building",
"code": "A",
"name": "buildingA"
},
"name": "A350.1"
},
{
"id": "2464",
"type": "student_group",
"code": "",
"name": ""
},
{
"id": "2747",
"type": "student_group",
"code": "",
"name": ""
}
],
"description": ""
}
]
}
In order to get the JSON response I need to put startDate (the moment user searches the vacant rooms, in this situation it is: 2017-04-27T10:55) and endDate (set to end of the day, 2017-04-27T22:00). The result for this query is the JSON response above.
The problem is that the API I'm using doesn't contain any data for the vacant rooms but only for the ones booked for certain times so I made a list of all the rooms in the building and compared it to the booked ones to filter them out:
var rooms = ['A120.3', 'A130.1', 'A130.3', 'A140.1', 'A140.2', 'A140.4', 'A250.1', 'A240.4', 'A240.2', 'A220.5', 'A220.3',
'A220.1', 'A210.2', 'A320.2', 'A320.6', 'A320.7', 'A320.8', 'A340.1', 'A340.2', 'A350.1', 'A350.3', 'A440.5', 'A450.3','A450.1',
'A440.4', 'A440.2', 'A420.6', 'A420.5', 'A420.4', 'A420.2', 'A510.2', 'A520.5', 'A510.4', 'A520.6', 'A520.7','A540.1', 'A540.2'];
var data = JSON.parse(responseText);
var booking = Object.create(null);
var free;
data.reservations.forEach(function (reservation) {
reservation.resources.some(function (resource) {
if (resource.type === 'room') {
booking[resource.code] = booking[resource.code] || [];
booking[resource.code].push({ startDate: reservation.startDate, endDate: reservation.endDate });
return true;
}
});
});
free = rooms.filter(function (a) {
return !booking[a];
});
console.log(free);
Results:
A210.3
A220.5
A320.2
A520.6
A510.4
This only returns the ones that are not being used at all during the day but I need to get the ones that are vacant for hour or two.
For this booked class for example:
"startDate": "2017-04-27T13:15:00",
"endDate": "2017-04-27T16:00:00",
"type": "room",
"code": "A520.5"
for this I would need to print out:
A520.5 - 2 hours 20 minutes
So I need to get the room / time from the startDate of the search (2017-04-27T10:55) and compare it to the startDate of the booked room (2017-04-27T13:15:00) to get the time remaining for that room to be vacant.
TO CLARIFY:
I have all the data for booked rooms starting from 2017-04-27T10:55
until 2017-04-27T22:00 as you can see from the JSON response above.
I need to somehow compare the startDate of the JSON query when the user
searches for the rooms (2017-04-27T10:55) and compare it to the booked
rooms startDate to get the time how long the room stays vacant.
This is how I'm doing my startDate and endDate for the JSON query:
// Timestamp needs to be formed (YYYY-MM-DDTxx:xx) in order for JSON query to work
var todaysDate = new Date();
function convertDate(date) {
var yyyy = date.getFullYear().toString();
var mm = (date.getMonth() + 1).toString();
var dd = date.getDate().toString();
var mmChars = mm.split('');
var ddChars = dd.split('');
return yyyy + '-' + (mmChars[1] ? mm : "0" + mmChars[0]) + '-' + (ddChars[1] ? dd : "0" + ddChars[0]);
}
// Current time when user searches for vacant rooms
var currentTime = new Date();
var time = "T" + currentTime.getHours() + ":" + currentTime.getMinutes();
// variables for the JSON query
var startDate = convertDate(todaysDate) + time;
var endDate = convertDate(todaysDate) + ("T22:00");
// JSON-query
var getRooms = {
"startDate": startDate,
"endDate": endDate
};

How can I access specific value of JSON object? [duplicate]

This question already has answers here:
How can I access and process nested objects, arrays, or JSON?
(31 answers)
Closed 6 years ago.
I can't seem to console.log the item name and just that. It's in the position data -> pricing -> tables -> items -> name. I am going for an output that says "Toy Panda".
[
{
"event": "recipient_completed",
"data": {
"id": "msFYActMfJHqNTKH8YSvF1",
"name": "Sample Document",
"status": "document.draft",
"date_created": "2014-10-06T08:42:13.836022Z",
"date_modified": "2016-03-04T02:21:13.963750Z",
"action_date": "2016-09-02T22:26:52.227554",
"action_by": {
"id": "FyXaS4SlT2FY7uLPqKD9f2",
"email": "john#appleseed.com",
"first_name": "John",
"last_name": "Appleseed"
},
"created_by": {
"id": "FyXaS4SlT2FY7uLPqKD9f2",
"email": "john#appleseed.com",
"first_name": "John",
"last_name": "Appleseed",
"avatar": "https://pd-live-media.s3.amazonaws.com/users/FyXaS4SlT2FY7uLPqKD9f2/avatar.jpg"
},
"recipients": [
{
"id": "FyXaS4SlT2FY7uLPqKD9f2",
"email": "john#appleseed.com",
"first_name": "John",
"last_name": "Appleseed",
"role": "signer",
"recipient_type": "Signer",
"has_completed": true
}
],
"sent_by": {
"id": "FyXaS4SlT2FY7uLPqKD9f2",
"email": "john#appleseed.com",
"first_name": "John",
"last_name": "Appleseed",
"avatar": "https://pd-live-media.s3.amazonaws.com/users/FyXaS4SlT2FY7uLPqKD9f2/avatar.jpg"
},
"metadata": {
"salesforce_opp_id": "123456",
"my_favorite_pet": "Panda"
},
"tokens": [
{
"name": "Favorite Animal",
"value": "Panda"
}
],
"fields": [
{
"uuid": "YcLBNUKcx45UFxAK3NjLIH",
"name": "Textfield",
"title": "Favorite Animal",
"value": "Panda",
"assigned_to": {
"id": "FyXaS4SlT2FY7uLPqKD9f2",
"email": "john#appleseed.com",
"first_name": "John",
"last_name": "Appleseed",
"role": "Signer",
"recipient_type": "signer",
"has_completed": true,
"type": "recipient"
}
}
],
"pricing": {
"tables": [
{
"id": 82307036,
"name": "PricingTable1",
"is_included_in_total": true,
"summary": {
"discount": 10,
"tax": 0,
"total": 60,
"subtotal": 60
},
"items": [
{
"id": "4ElJ4FEsG4PHAVNPR5qoo9",
"qty": 1,
"name": "Toy Panda",
"cost": "25",
"price": "53",
"description": "Buy a Panda",
"custom_fields": {
"sampleField": "Sample Field"
},
"custom_columns": {
"sampleColumn": "Sample Column"
},
"discount": 10,
"subtotal": 60
}
],
"total": 60
}
]
},
"tags": [
"test tag",
"sales",
"support"
]
}
}
]
I would really appreciate a tip. Thank you

If you store your JSON object into variable called obj you can access that value ("Toy Panda") with:
obj.data.pricing.tables[0].items[0].name
because tables and items are arrays.

Here is a sample example :
<script>
var data = '{"name": "mkyong","age": 30,"address": {"streetAddress": "88 8nd Street","city": "New York"},"phoneNumber": [{"type": "home","number": "111 111-1111"},{"type": "fax","number": "222 222-2222"}]}';
var json = JSON.parse(data);
alert(json["name"]); //mkyong
alert(json.name); //mkyong
</script>
Refer this link :[https://www.mkyong.com/javascript/how-to-access-json-object-in-javascript/][1]
In your case it should be something like :
var data = // your json;
var json = JSON.parse(data);
console.log(json.pricing.tables.items[0].name;

Kendo UI HierarchicalDataSource for Treeview with dynamic schema

I'm trying to display a Kendo treeview thanks to a HierarchicalDataSource.
It's a simple region, country, city hierarchy but the difficulty comes with the fact that we have 3 possible levels of regions and countries can appear at the second or at the third level.
Basically,
- First level of regions contains only other regions
- Second level of regions contains other regions or countries
- Third level of regions contains only countries
Here are my schemas:
var portsSchema = {
schema: {
data: "PortList",
model: {
id: "Code"
}
}
};
var countrySchema = {
schema: {
data: "CountryList",
model: {
id: "Code",
children: portsSchema
}
}
};
var regionCountrySchema = {
schema: {
data: "RegionList",
model: {
id: "id",
children: countrySchema
}
}
};
var regionSchema = {
schema: {
data: "RegionList",
model: {
id: "id",
children: regionCountrySchema
}
}
};
Depending on the fact that the region has countries or not, I would like to specify a specific type of children (regionSchema or regionCountrySchema).
var tvDataSource = new kendo.data.HierarchicalDataSource({
data: regions,
schema: {
model: function (data) {
**how to return the right children schema ?**
}
}
});
Returning { children: regionSchema } or {children: regionCountrySchema } triggers a js kendo error.
Any idea to achieve this ? Thank you.
JSON data sample below.
[
{
"Id": 1,
"Name": "MIDDLE EAST AND RED SEA",
"RegionList": [
{
"Id": 12,
"Name": "MIDDLE EAST",
"RegionList": [
{
"Id": 45,
"Name": "M. EAST",
"RegionList": [
],
"CountryList": [
{
"Id": 12007,
"Code": "AE",
"Name": "UAE",
"PortList": [
{
"Id": 6005,
"Code": "AEJEA",
"Name": "JEBEL ALI"
},
{
"Id": 16014,
"Code": "AEAJM",
"Name": "AJMAN"
},
{
"Id": 16015,
"Code": "AEAUH",
"Name": "ABU DHABI"
},
{
"Id": 15109,
"Code": "AEKLF",
"Name": "KHOR AL FAKKAN"
},
{
"Id": 15001,
"Code": "AERKT",
"Name": "RAS AL KHAIMAH"
},
{
"Id": 16018,
"Code": "AESHJ",
"Name": "SHARJAH"
},
{
"Id": 14863,
"Code": "AEQIW",
"Name": "UMM AL QAIWAIN"
},
{
"Id": 15647,
"Code": "AEFJR",
"Name": "AL - FUJAYRAH"
}
]
},
{
"Id": 12018,
"Code": "OM",
"Name": "OMAN",
"PortList": [
{
"Id": 6011,
"Code": "OMSLL",
"Name": "SALALAH"
},
{
"Id": 16218,
"Code": "OMSOH",
"Name": "SOHAR"
}
]
},
{
"Id": 10069,
"Code": "BH",
"Name": "BAHRAIN",
"PortList": [
{
"Id": 15345,
"Code": "BHKBS",
"Name": "BAHRAIN"
}
]
},
{
"Id": 62292,
"Code": "IQ",
"Name": "IRAQ",
"PortList": [
{
"Id": 15383,
"Code": "IQBSR",
"Name": "BASRA"
},
{
"Id": 14673,
"Code": "IQUQR",
"Name": "UMM QASR PT"
}
]
},
{
"Id": 62291,
"Code": "IR",
"Name": "IRAN, ISLAMIC REPUBLIC OF",
"PortList": [
{
"Id": 15250,
"Code": "IRBKM",
"Name": "BANDAR KHOMEINI"
},
{
"Id": 15249,
"Code": "IRBND",
"Name": "BANDAR ABBAS"
},
{
"Id": 14973,
"Code": "IRBUZ",
"Name": "BUSHEHR"
},
{
"Id": 14671,
"Code": "IRKHO",
"Name": "KHORRAMSHAHR"
}
]
},
{
"Id": 62306,
"Code": "KW",
"Name": "KUWAIT",
"PortList": [
{
"Id": 15810,
"Code": "KWSAA",
"Name": "SHUAIBA"
},
{
"Id": 15811,
"Code": "KWSWK",
"Name": "SHUWAIKH"
}
]
},
{
"Id": 12002,
"Code": "SA",
"Name": "SAUDI ARABIA",
"PortList": [
{
"Id": 15039,
"Code": "SAJUB",
"Name": "JUBAIL"
},
{
"Id": 16147,
"Code": "SADMM",
"Name": "AD DAMMAM"
}
]
},
{
"Id": 62364,
"Code": "QA",
"Name": "QATAR",
"PortList": [
{
"Id": 15739,
"Code": "QADOH",
"Name": "DOHA"
},
{
"Id": 14795,
"Code": "QAMES",
"Name": "MESAIEED"
}
]
}
]
}
],
"CountryList": [
]
},
{
"Id": 30,
"Name": "RED SEA",
"RegionList": [
{
"Id": 65,
"Name": "RED SEA",
"RegionList": [
],
"CountryList": [
]
}
],
"CountryList": [
{
"Id": 12002,
"Code": "SA",
"Name": "SAUDI ARABIA",
"PortList": [
{
"Id": 6003,
"Code": "SAKAC",
"Name": "KING ABDULLAH PORT"
},
{
"Id": 15731,
"Code": "SAJED",
"Name": "JEDDAH"
}
]
},
{
"Id": 10114,
"Code": "DJ",
"Name": "DJIBOUTI",
"PortList": [
{
"Id": 8059,
"Code": "DJJIB",
"Name": "DJIBOUTI"
}
]
},
{
"Id": 10122,
"Code": "ER",
"Name": "ERITREA",
"PortList": [
{
"Id": 15031,
"Code": "ERMSW",
"Name": "MASSAWA"
}
]
},
{
"Id": 62300,
"Code": "JO",
"Name": "JORDAN",
"PortList": [
{
"Id": 14801,
"Code": "JOAQJ",
"Name": "AL \u0027AQABAH"
}
]
},
{
"Id": 50001,
"Code": "SD",
"Name": "sd",
"PortList": [
{
"Id": 15734,
"Code": "SDPZU",
"Name": "PORT SUDAN"
}
]
},
{
"Id": 62425,
"Code": "YE",
"Name": "YEMEN",
"PortList": [
{
"Id": 15302,
"Code": "YEHOD",
"Name": "HODEIDAH"
},
{
"Id": 15304,
"Code": "YEMKX",
"Name": "MUKALLA"
},
{
"Id": 15300,
"Code": "YEADE",
"Name": "ADEN"
}
]
},
{
"Id": 10118,
"Code": "EG",
"Name": "EGYPT",
"PortList": [
{
"Id": 16030,
"Code": "EGSOK",
"Name": "SOKHNA PORT"
}
]
}
]
}
],
"CountryList": [
]
}
]

How can i get the total count id of this collection using javascript?

I have this collection: https://graph.facebook.com/2playcz/albums
This collection contains 8 id. How can i get the total count id of this collection using javascript? (Total = 8)
Source:
{
"data": [
{
"id": "201936779932071",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Tr\u00e9ninky",
"link": "https://www.facebook.com/album.php?fbid=201936779932071&id=190320081093741&aid=41883",
"cover_photo": "201937046598711",
"count": 8,
"type": "normal",
"created_time": "2012-07-02T09:33:43+0000",
"updated_time": "2012-09-15T12:05:44+0000",
"can_upload": false,
"likes": {
"data": [
{
"id": "1788805921",
"name": "Edita Nov\u00e1"
},
{
"id": "100001449904219",
"name": "Mirka Brani\u0161ov\u00e1"
}
],
"paging": {
"next": "https://graph.facebook.com/201936779932071/likes?limit=25&offset=25&__after_id=100001449904219"
}
}
},
{
"id": "205206429605106",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Turnaje a akce",
"link": "https://www.facebook.com/album.php?fbid=205206429605106&id=190320081093741&aid=42900",
"cover_photo": "205208716271544",
"count": 14,
"type": "normal",
"created_time": "2012-07-10T19:36:53+0000",
"updated_time": "2012-09-15T12:04:05+0000",
"can_upload": false
},
{
"id": "221784994613916",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Tenisova \u0161kolka 2play",
"description": "Tenisov\u00e1 \u0161kolka 2play",
"link": "https://www.facebook.com/album.php?fbid=221784994613916&id=190320081093741&aid=49379",
"cover_photo": "221785024613913",
"count": 9,
"type": "normal",
"created_time": "2012-08-31T11:19:59+0000",
"updated_time": "2012-09-14T15:17:53+0000",
"can_upload": false
},
{
"id": "203405996451816",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Webov\u00e9 fotografie - Logo",
"link": "https://www.facebook.com/album.php?fbid=203405996451816&id=190320081093741&aid=42285",
"cover_photo": "203406586451757",
"count": 11,
"type": "normal",
"created_time": "2012-07-05T10:12:40+0000",
"updated_time": "2012-09-14T15:16:40+0000",
"can_upload": false
},
{
"id": "190332361092513",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Cover Photos",
"link": "https://www.facebook.com/album.php?fbid=190332361092513&id=190320081093741&aid=39232",
"cover_photo": "225939404198475",
"count": 2,
"type": "normal",
"created_time": "2012-06-09T13:52:38+0000",
"updated_time": "2012-09-12T18:15:51+0000",
"can_upload": false
},
{
"id": "190802884378794",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Wall Photos",
"link": "https://www.facebook.com/album.php?fbid=190802884378794&id=190320081093741&aid=39324",
"cover_photo": "190802891045460",
"count": 2,
"type": "wall",
"created_time": "2012-06-10T13:19:48+0000",
"updated_time": "2012-07-17T17:16:19+0000",
"can_upload": false
},
{
"id": "205207126271703",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Ostatn\u00ed",
"link": "https://www.facebook.com/album.php?fbid=205207126271703&id=190320081093741&aid=42902",
"cover_photo": "205209679604781",
"count": 4,
"type": "normal",
"created_time": "2012-07-10T19:40:05+0000",
"updated_time": "2012-07-16T14:47:16+0000",
"can_upload": false,
"likes": {
"data": [
{
"id": "100001449904219",
"name": "Mirka Brani\u0161ov\u00e1"
}
],
"paging": {
"next": "https://graph.facebook.com/205207126271703/likes?limit=25&offset=25&__after_id=100001449904219"
}
}
},
{
"id": "190320914426991",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Profile Pictures",
"link": "https://www.facebook.com/album.php?fbid=190320914426991&id=190320081093741&aid=39224",
"cover_photo": "190327474426335",
"count": 1,
"type": "profile",
"created_time": "2012-06-09T13:29:16+0000",
"updated_time": "2012-06-09T13:43:08+0000",
"can_upload": false
},
{
"id": "190322704426812",
"from": {
"name": "2play.cz - Tenisov\u00e1 \u0161kola",
"category": "Sports league",
"id": "190320081093741"
},
"name": "Logo",
"description": "Loga spole\u010dnosti",
"link": "https://www.facebook.com/album.php?fbid=190322704426812&id=190320081093741&aid=39225",
"type": "normal",
"created_time": "2012-06-09T13:34:09+0000",
"updated_time": "2012-07-05T10:16:58+0000",
"can_upload": false
}
]
}

If you mean the count of items in the data array, it would just be data.length.

First of all, there 9 ids. If you want to count the number of elements in array there's a built-in property length. So that if your object is called x you retrieve the length of data by accessing x.data.length.
On the other hand, if you wanted to count the number of unique ids (IDs should by unique anyway, but if you really really wanted to) you have to manually iterate through the array and count them:
var countIds = function (arr) {
var uniqueIds = {}, num = 0;
if (!arr.data) return false;
arr.data.forEach(function (val, i) {
if (typeof uniqueIds[val.id] === "undefined") {
++num;
uniqueIds[val.id] = true;
}
});
return num;
};

Extracting data from JSON using javascript

I have JSON similar to this . I wish to extract values like name, his id, and product title from this list . But I am not able to figure it out . I was trying "eval" for the same.
{
"data": [{
"id": "3092773937557",
"from": {
"id": "1810306393",
"name": "Prashant Singh"
},
"start_time": "2012-07-21T09:12:53+0000",
"end_time": "2012-07-21T09:12:53+0000",
"publish_time": "2012-07-21T09:12:53+0000",
"application": {
"id": "132692593533721",
"name": "Compare Hatke"
},
"data": {
"productname": "Apple iPod Nano",
"price": 399,
"product": {
"id": "10151004296768984",
"url": "http:\/\/compare.buyhatke.com\/products\/Apple-iPod-Nano",
"type": "comparehatke:product",
"title": "Apple iPod Nano"
}
},
"likes": {
"count": 0
},
"comments": {
"count": 0
},
"no_feed_story": false
}, {
"id": "3092770217464",
"from": {
"id": "1810306393",
"name": "Prashant Singh"
},
"start_time": "2012-07-21T09:08:53+0000",
"end_time": "2012-07-21T09:08:53+0000",
"publish_time": "2012-07-21T09:08:53+0000",
"application": {
"id": "132692593533721",
"name": "Compare Hatke"
},
"data": {
"productname": "Apple iPod Nano",
"price": 399,
"product": {
"id": "10151004296768984",
"url": "http:\/\/compare.buyhatke.com\/products\/Apple-iPod-Nano",
"type": "comparehatke:product",
"title": "Apple iPod Nano"
}
},
"likes": {
"count": 0
},
"comments": {
"count": 0
},
"no_feed_story": false
}],
"paging": {
"next": "https:\/\/graph.facebook.com\/me\/comparehatke:compare\/?access_token=AAAB4rubm4xkBAHRhdjVgx7JxIIvUxImIm31AMxgnqEAOQsAsgZAJjBYUfvzKc8XgxDBg3AzKN1S6QU2dnmtgj7TPcoCiih1RzrL3pLpuZAgGt8eKpq&limit=2&method=get&pretty=0&offset=2"
}
}

<html>
<script style="text/javscript">
var myObject = { "data": [{
"id": "3092741696751",
"from": {
"id": "1810306393",
"name": "Prashant Singh"
},
"start_time": "2012-07-21T08:40:38+0000",
"end_time": "2012-07-21T08:40:38+0000",
"publish_time": "2012-07-21T08:40:38+0000",
"application": {
"id": "132692593533721",
"name": "Compare Hatke"
},
"data1": {
"productname": "Apple iPod Nano",
"price": 399,
"product": {
"id": "10151004296768984",
"url": "http:\/\/compare.buyhatke.com\/products\/Apple-iPod-Nano",
"type": "comparehatke:product",
"title": "Apple iPod Nano"
}
},
"likes": {
"count": 0
},
"comments": {
"count": 0
},
"no_feed_story": false
} ]};
alert(myObject.data[0].id);
</script>
</html>

data = JSON.parse(yourJSONString);
If this fails, you likely have an error in your JSON. You can use http://jsonlint.com/ to find and resolve the problem. In the paste above, you're missing your closing ]}.