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C#

Google Contacts - Retrieve as JSON

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Demonstrates how to retrieve Google Contacts as JSON.

Chilkat C# Downloads

C#
bool success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// --------------------------------------------------------------------------------------------------------
// Note: The code for setting up the Chilkat REST object and making the initial connection can be done once.
// Once connected, the REST object may be re-used for many REST API calls.
// (It's a good idea to put the connection setup code in a separate function/subroutine.)
// --------------------------------------------------------------------------------------------------------

// It is assumed we previously obtained an OAuth2 access token.
// This example loads the JSON access token file 
// saved by this example: Get Google Contacts OAuth2 Access Token

Chilkat.JsonObject jsonToken = new Chilkat.JsonObject();
success = jsonToken.LoadFile("qa_data/tokens/googleContacts.json");
if (success != true) {
    Debug.WriteLine("Failed to load googleContacts.json");
    return;
}

Chilkat.AuthGoogle gAuth = new Chilkat.AuthGoogle();
gAuth.AccessToken = jsonToken.StringOf("access_token");

Chilkat.Rest rest = new Chilkat.Rest();

// Connect using TLS.
bool bAutoReconnect = true;
success = rest.Connect("www.google.com",443,true,bAutoReconnect);

// Provide the authentication credentials (i.e. the access token)
rest.SetAuthGoogle(gAuth);

// ----------------------------------------------
// OK, the REST connection setup is completed..
// ----------------------------------------------

// To retrieve the contacts, we need to send the following:

// 	GET /m8/feeds/contacts/default/full
// 	GData-Version: 3.0

// To get the contacts data in JSON format, set the "alt" query parameter to "json"
rest.AddQueryParam("alt","json");
rest.AddHeader("GData-Version","3.0");

Chilkat.StringBuilder sbResponseBody = new Chilkat.StringBuilder();
success = rest.FullRequestNoBodySb("GET","/m8/feeds/contacts/default/full",sbResponseBody);
if (success != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// A successful response will have a status code equal to 200.
if (rest.ResponseStatusCode != 200) {
    Debug.WriteLine("response status code = " + Convert.ToString(rest.ResponseStatusCode));
    Debug.WriteLine("response status text = " + rest.ResponseStatusText);
    Debug.WriteLine("response header: " + rest.ResponseHeader);
    Debug.WriteLine("response body: " + sbResponseBody.GetAsString());
    return;
}

// If the 200 response was received, then the contacts JSON is contained
// in the response body.
Chilkat.JsonObject json = new Chilkat.JsonObject();
json.LoadSb(sbResponseBody);
json.EmitCompact = false;

// Save the pretty-printed JSON response to a file.
sbResponseBody.Clear();
json.EmitSb(sbResponseBody);
sbResponseBody.WriteFile("qa_output/google_contacts.json","utf-8",false);

// Parse the Google Contacts JSON, and iterate over the contacts..
int totalResults = json.IntOf("feed.openSearch$totalResults.$t");
int startIndex = json.IntOf("feed.openSearch$startIndex.$t");
int itemsPerPage = json.IntOf("feed.openSearch$itemsPerPage.$t");
Debug.WriteLine("totalResults = " + Convert.ToString(totalResults));
Debug.WriteLine("startIndex = " + Convert.ToString(startIndex));
Debug.WriteLine("itemsPerPage = " + Convert.ToString(itemsPerPage));

int numEntries = json.SizeOfArray("feed.entry");
int i = 0;
while (i < numEntries) {
    json.I = i;
    Debug.WriteLine(Convert.ToString(i + 1) + " ----");
    Debug.WriteLine("title: " + json.StringOf("feed.entry[i].title.$t"));

    string fullName = json.StringOf("feed.entry[i].gd$name.gd$fullName.$t");
    if (json.LastMethodSuccess == true) {
        Debug.WriteLine("fullName: " + fullName);
    }

    // There can be multiple email addresses, so it's stored as a JSON array..
    int numEmailAddresses = json.SizeOfArray("feed.entry[i].gd$email");
    int j = 0;
    while (j < numEmailAddresses) {
        string emailAddress = json.StringOf("feed.entry[i].gd$email[j].address");
        if (json.LastMethodSuccess == true) {
            Debug.WriteLine("email address: " + emailAddress);
        }

        j = j + 1;
    }

    i = i + 1;
}

// A sample Google Contacts JSON response:

// 	{ 
// 	  "version": "1.0",
// 	  "encoding": "UTF-8",
// 	  "feed": { 
// 	    "xmlns": "http://www.w3.org/2005/Atom",
// 	    "xmlns$openSearch": "http://a9.com/-/spec/opensearch/1.1/",
// 	    "xmlns$gContact": "http://schemas.google.com/contact/2008",
// 	    "xmlns$batch": "http://schemas.google.com/gdata/batch",
// 	    "xmlns$gd": "http://schemas.google.com/g/2005",
// 	    "gd$etag": "\"QHw5eTVSLyt7I2A9XRFaE0kNTwI.\"",
// 	    "id": { 
// 	      "$t": "chilkat.support@gmail.com"
// 	    },
// 	    "updated": { 
// 	      "$t": "2016-11-17T01:57:41.221Z"
// 	    },
// 	    "category": [
// 	      { 
// 	        "scheme": "http://schemas.google.com/g/2005#kind",
// 	        "term": "http://schemas.google.com/contact/2008#contact"
// 	      }
// 	    ],
// 	    "title": { 
// 	      "$t": "Chilkat Support's Contacts"
// 	    },
// 	    "link": [
// 	      { 
// 	        "rel": "alternate",
// 	        "type": "text/html",
// 	        "href": "https://www.googleapis.com/"
// 	      },
// 	      { 
// 	        "rel": "http://schemas.google.com/g/2005#feed",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
// 	      },
// 	      { 
// 	        "rel": "http://schemas.google.com/g/2005#post",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
// 	      },
// 	      { 
// 	        "rel": "http://schemas.google.com/g/2005#batch",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/batch"
// 	      },
// 	      { 
// 	        "rel": "self",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json"
// 	      },
// 	      { 
// 	        "rel": "next",
// 	        "type": "application/atom+xml",
// 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json&start-index=26"
// 	      }
// 	    ],
// 	    "author": [
// 	      { 
// 	        "name": { 
// 	          "$t": "Chilkat Support"
// 	        },
// 	        "email": { 
// 	          "$t": "chilkat.support@gmail.com"
// 	        }
// 	      }
// 	    ],
// 	    "generator": { 
// 	      "version": "1.0",
// 	      "uri": "http://www.google.com/m8/feeds",
// 	      "$t": "Contacts"
// 	    },
// 	    "openSearch$totalResults": { 
// 	      "$t": "350"
// 	    },
// 	    "openSearch$startIndex": { 
// 	      "$t": "1"
// 	    },
// 	    "openSearch$itemsPerPage": { 
// 	      "$t": "25"
// 	    },
// 	    "entry": [
// 	      { 
// 	        "id": { 
// 	          "$t": "http://www.google.com/m8/feeds/contacts/chilkat.support%40gmail.com/base/0"
// 	        },
// 	        "gd$etag": "\"SX8zcTVSLyt7I2A9WxBXFU4MQwI.\"",
// 	        "updated": { 
// 	          "$t": "2010-01-26T20:07:48.189Z"
// 	        },
// 	        "app$edited": { 
// 	          "xmlns$app": "http://www.w3.org/2007/app",
// 	          "$t": "2010-01-26T20:07:48.189Z"
// 	        },
// 	        "category": [
// 	          { 
// 	            "scheme": "http://schemas.google.com/g/2005#kind",
// 	            "term": "http://schemas.google.com/contact/2008#contact"
// 	          }
// 	        ],
// 	        "title": { 
// 	          "$t": "Joe Sample"
// 	        },
// 	        "link": [
// 	          { 
// 	            "rel": "http://schemas.google.com/contacts/2008/rel#photo",
// 	            "type": "image/*",
// 	            "href": "https://www.googleapis.com/m8/feeds/photos/media/chilkat.support%40gmail.com/0"
// 	          },
// 	          { 
// 	            "rel": "self",
// 	            "type": "application/atom+xml",
// 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
// 	          },
// 	          { 
// 	            "rel": "edit",
// 	            "type": "application/atom+xml",
// 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
// 	          }
// 	        ],
// 	        "gd$name": { 
// 	          "gd$fullName": { 
// 	            "$t": "Joe Sample"
// 	          },
// 	          "gd$givenName": { 
// 	            "$t": "Joe"
// 	          },
// 	          "gd$familyName": { 
// 	            "$t": "Sample"
// 	          }
// 	        },
// 	        "gd$email": [
// 	          { 
// 	            "address": "somebody@gmail.com",
// 	            "primary": "true",
// 	            "rel": "http://schemas.google.com/g/2005#other"
// 	          }
// 	        ]
// 	      },
// 		... more entries ...
//