how to implement code for JSON parsing getting response into the NSArray?

Question

How is the iphone code for getting below response into the array? Here I need to store contents "Id value", "LastUpdated value" and "Title" these three values need to be stored in 3 different arrays how it is possible?

Here is the response:

[
    {
        "Contents": [
            {
                "Id": 381,
                "LastUpdated": "/Date(1338347251003+0000)/",
                "Title": "Forrester Study - Total Economic Impact of Lync",
                "Url": "http://infra2apps.blob.core.windows.net/eventapp/Forrester Study - Total Economic Impact of Lync_booth1.pdf"
            }
        ],
        "Id": 1,
        "ImageUrl": "http://infra2apps.blob.core.windows.net/eventapp/Lync.png",
        "Name": "Unified Communications & Collaborations",
        "Sessions": [
            {
                "Description": "Microsoft Lync delivers Unified Communications to help people connect in new ways, anytime, anywhere.  Learn how HP and Microsoft are helping customers transform their business infrastructure and gain greater productivity by making every communication an interaction that is more collaborative and engaging.",
                "EndDate": "/Date(1338922800000+0000)/",
                "FriendlyName": "TB3257",
                "Id": 1,
                "Location": "TBD",
                "Speakers": [
                    {
                        "Company": "Microsoft",
                        "Email": "ashimas@microsoft.com",
                        "Name": "Ashima Singhal",
                        "Title": "Group Marketing Manager, Lync"
                    },
                    {
                        "Company": "HP",
                        "Email": "dragana.beara@hp.com",
                        "Name": "Dragana Beara",
                        "Title": "HP"
                    }
                ],
                "StartDate": "/Date(1338920100000+0000)/",
                "Title": "Connecting People in New Ways with Microsoft Lync"
            }
        ]
    },
    {
        "Contents": [
            {
                "Id": 385,
                "LastUpdated": "/Date(1338347251143+0000)/",
                "Title": "Windows 8 Consumer Preview - Product Guide - Business",
                "Url": "http://infra2apps.blob.core.windows.net/eventapp/Windows 8 Consumer Preview - Product Guide - Business_booth2.pdf"
            },
            {
                "Id": 383,
                "LastUpdated": "/Date(1338347251080+0000)/",
                "Title": "Mitigating Risk - Why Sticking with Windows XP is a Bad Idea",
                "Url": "http://infra2apps.blob.core.windows.net/eventapp/Mitigating Risk - Why Sticking with Windows XP is a Bad Idea - IDC - May 2012_booth2.pdf"
            }
        ],
        "Id": 2,
        "ImageUrl": "http://infra2apps.blob.core.windows.net/eventapp/Windows-brand.png",
        "Name": "Windows the right choice for business",
        "Sessions": [
            {
                "Description": "Microsoft and HP are partnering together to migrate customers to Windows 7 while working closely together to build new Windows 8 products that will easily integrate into a Windows 7 environment.   This session provides insight on how these new offerings will provide enterprise grade solutions with no compromise business devices that increase productivity, security, and manageability and the path to get there.",
                "EndDate": "/Date(1338935400000+0000)/",
                "FriendlyName": "TB3256",
                "Id": 3,
                "Location": "TBD",
                "Speakers": [
                    {
                        "Company": "Microsoft",
                        "Email": "snagy@microsoft.com",
                        "Name": "Sara Nagy",
                        "Title": "Senior Account Manager - OEM"
                    }
                ],
                "StartDate": "/Date(1338932700000+0000)/",
                "Title": "Preparing for Windows 8"
            }
        ]
    },
    {
        "Contents": [
            {
                "Id": 382,
                "LastUpdated": "/Date(1338347251043+0000)/",
                "Title": "HP EDW Appliance Solution Brief",
                "Url": "http://infra2apps.blob.core.windows.net/eventapp/HP EDW Appliance Solution Brief_booth3.pdf"
            },
            {
                "Id": 380,
                "LastUpdated": "/Date(1338347250970+0000)/",
                "Title": "HP DBCA Datasheet",
                "Url": "http://infra2apps.blob.core.windows.net/eventapp/11475_DBCA-Datasheet_booth3.pdf"
            }
        ],
        "Id": 3,
        "ImageUrl": "http://infra2apps.blob.core.windows.net/eventapp/SQL.png",
        "Name": "Enterprise Information Platform",
        "Sessions": [
            {
                "Description": "The Database Consolidation appliance integrates software and harware into a turnkey solution that creates tremendous opportunities to virtualize demanding applications requiring enterprise-class resiliency. This session will dive into this NEW Private Cloud Appliance, leveraging virtualization and tuned and balanced infrastructure to deliver Private Cloud capabilities. We’ll go into detail including how to inventory and gather performance characteristics to provide detailed appliance-specific sizing and placement guidance using the MAP toolkit, how the appliance architecture enables high IO performance, isolation. and resiliency, and into details around core operational capabilities such as P-to-V and self-service workflow-enabled provisioning of new instances. Also, we will cover advanced capabilities such as chargeback, sustained engineering (upgrades and patching), load balancing with Live Demos that will show off the core capabilities of the appliance.",
                "EndDate": "/Date(1339017300000+0000)/",
                "FriendlyName": "TB3323",
                "Id": 5,
                "Location": "TBD",
                "Speakers": [
                    {
                        "Company": "Microsoft",
                        "Email": "markmort@microsoft.com",
                        "Name": "Mark Mortimore",
                        "Title": "Senior Program Manager, SQL Server Appliances"
                    }
                ],
                "StartDate": "/Date(1339014600000+0000)/",
                "Title": "Cloud on your terms - Database Consolidation Appliance"
            },
            {
                "Description": "Leveraging virtual and scalable infrastructure - 100s of servers can be efficiently, reliably, and manageably consolidated. This session will dive into the NEW DBC Appliance, leveraging virtualization and tuned and balanced infrastructure.  Using demos, we will show all phases of consolidation including how to assess environments using the MAP toolkit, details around core operational capabilities such as P-to-V and self-service workflow-enabled provisioning of new fully configured servers.  Also, we will cover advanced capabilities such as chargeback, s load balancing…  ",
                "EndDate": "/Date(1339006800000+0000)/",
                "FriendlyName": "DT3324",
                "Id": 6,
                "Location": "TBD",
                "Speakers": [
                    {
                        "Company": "Microsoft",
                        "Email": "markmort@microsoft.com",
                        "Name": "Mark Mortimore",
                        "Title": "Senior Program Manager, SQL Server Appliances"
                    }
                ],
                "StartDate": "/Date(1339005600000+0000)/",
                "Title": "Database Consolidation & Private Cloud Appliance"
            }
        ]
    },
    {
        "Contents": [],
        "Id": 4,
        "ImageUrl": "http://infra2apps.blob.core.windows.net/eventapp/WinStorageSvr.png",
        "Name": "Windows Storage Server",
        "Sessions": []
    },
    {
        "Contents": [],
        "Id": 5,
        "ImageUrl": "http://infra2apps.blob.core.windows.net/eventapp/SQL.png",
        "Name": "Platform Modernization/Migration",
        "Sessions": [
            {
                "Description": "Microsoft and HP engineering have collaborated on delivering mission critical systems which outperform historic tier 1 platforms.   Although many companies rely on the combination of HP and Microsoft for Mission Critical workloads, there has been a lingering doubt that the combined platform can scale to the needs of large enterprises currently relying on IBM Mainframes.  This session will describe a signficant study just completed that puts to rest the myths that mainframes are the only platform that scales, can support high-IO and delivery mission critical capabilities.  Finally an apples to apples comparison that you can use as you modernize your IT enviornment.",
                "EndDate": "/Date(1339093200000+0000)/",
                "FriendlyName": "DT3471",
                "Id": 8,
                "Location": "TBD",
                "Speakers": [
                    {
                        "Company": "Microsoft",
                        "Email": "scorosen@microsoft.com",
                        "Name": "Scott Rosenbloom",
                        "Title": "SSP Platform Modernization"
                    }
                ],
                "StartDate": "/Date(1339092000000+0000)/",
                "Title": "Mainframe Alternative: Windows Server, SQL Server and HP DL 980"
            }
        ]
    }
]

Answer 1

Your response is no valid JSON. You cannot parse it using standard JSON Parsers. (You can use http://jsonlint.com/ for validating.)

//edit: So after your edit you do have valid JSON data. To parse it you can use any JSON Parsing Framework you find (a popular one eg is the json-framework ).

But if you are building for iOS5 only, you can use the system library NSJSONSerialization .

Answer 2

If you target iOS 5 or greater, JSON support is native, so you don't need to add any external libraries or implement the parser. You just use NSJSONSerialization.

See the documentation

Example code:

NSError* error = nil;

NSArray* parsed = [NSJSONSerialization JSONObjectWithData:data options:0 error:&error];

if(!error) {
    //Process here
}

If you target iOS versions lower than iOS 5 then JSON parsing is not supported natively and you must implement parser yourself, or use an external library fitting your needs. Example of libraries: SBJSON

Answer 3

Sorry for not explaining the below code due to time issue

-(void) dataRecieved: (NSDictionary *) receivedDict
{
 NSArray *contentsArray = [receivedDict objectForKey:@"Contents"];
 NSArray *sessionsArray = [receivedDict objectForKey:@"Sessions"];

 for (NSDictionary *contentsDict in contentsArray )
    {
        Contents *objContents = [[Contents alloc]init];
        objContents.id = [contentsDict objectForKey:@"ID"];
        objContents.lastUpdate = [contentsDict objectForKey:@"LastUpdate"];
        objContents.title = [contentsDict objectForKey:@"Title"];

        [contentObjectsArray addObject: objContents]; 
    }

    for (NSDictionary *sessionsDict in sessionsArray )
    {
        Sessions *objSessions = [[Sessions alloc]init];
        objSessions.id = [contentsDict objectForKey:@"ID"];
        objSessions.endDate = [contentsDict objectForKey:@"EndDate"];

        NSArray *speakersArray = [receivedDict objectForKey:@"Speakers"];

        for (NSDictionary *spearkersDict in speakersArray )
        {
            Speakers *objSpeakers = [[Speakers alloc]init];
            objSpeakers.title = [spearkersDict objectForKey:@"Title"];
            [objSessions.speakerssObjectsArray addObject: objSpeakers];
        }

        [sessionsObjectsArray addObject:objSessions]; 
    }
}

Answer 4

使用SBJsonParser解析JSON，您可以使用此链接可视化JSON，以便您可以知道将在何处使用哪种数据结构，其余的就像@imsult所说的那样。