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C#

Find Contact Having Email Address

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Demonstrates how to fetch the Google Contact for a given email address.

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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?q=<emailAddress>
// 	GData-Version: 3.0

// Get the contact (or contacts) with this email address:
string emailAddressToFind = "admin@chilkatsoft.com";

rest.AddHeader("GData-Version","3.0");
rest.AddQueryParam("q",emailAddressToFind);

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 XML is contained
// in the response body.
Chilkat.Xml xml = new Chilkat.Xml();
xml.LoadSb(sbResponseBody,false);

// See below for a sample response body.
xml.SaveXml("qa_output/google_contacts.xml");

// Now let's parse the XML...

// Get the the total number of results, the start index, and the items per page.
// We'll likely NOT get the full list, but will instead get the 1st page.
int totalResults = xml.GetChildIntValue("openSearch:totalResults");
int startIndex = xml.GetChildIntValue("openSearch:startIndex");
int itemsPerPage = xml.GetChildIntValue("openSearch:itemsPerPage");
Debug.WriteLine("totalResults = " + Convert.ToString(totalResults));
Debug.WriteLine("startIndex = " + Convert.ToString(startIndex));
Debug.WriteLine("itemsPerPage = " + Convert.ToString(itemsPerPage));

// We'll borrow a method from FileAccess to get the contactId from the URL string (see the code in the while loop)
Chilkat.FileAccess fac = new Chilkat.FileAccess();

// Iterate over each contact.
int numEntries = xml.NumChildrenHavingTag("entry");
int i = 0;
while (i < numEntries) {
    xml.I = i;
    Debug.WriteLine(Convert.ToString(i + 1) + " ----");
    Debug.WriteLine("title: " + xml.GetChildContent("entry[i]|title"));

    // The entry "id" child contains a URL having this format:
    // <id>http://www.google.com/m8/feeds/contacts/{userEmail}/base/{contactId}</id>
    // Let's get the URL and parse the contactId from it..
    string idUrl = xml.GetChildContent("entry[i]|id");
    Debug.WriteLine("id: " + idUrl);

    // Use the parsing ability of GetFileName to get the contactId
    string contactId = fac.GetFileName(idUrl);
    Debug.WriteLine("contactId: " + contactId);

    string fullName = xml.ChilkatPath("entry[i]|gd:name|gd:fullName|*");
    if (xml.LastMethodSuccess == true) {
        Debug.WriteLine("fullName: " + fullName);
    }

    string emailAddress = xml.ChilkatPath("entry[i]|gd:email|(address)");
    if (xml.LastMethodSuccess == true) {
        Debug.WriteLine("email address: " + emailAddress);
    }

    i = i + 1;
}