C#

GMail IMAP Authentication using OAuth2 Access Token

See more GMail SMTP/IMAP/POP Examples

Demonstrates how to do IMAP OAuth2 authentication for GMail (or any other IMAP mail server supporting OAuth2 authentication). This example assumes an OAuth2 access token was previously obtained. C#

bool success = false;

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

// See Get GMail IMAP OAuth2 Access Token for Desktop App 
// for sample code showing how to obtain a GMail IMAP read/write access token.

// In this example, our access token was previously saved to the following file which contains JSON like this:
// 	{
// 	 "access_token": "ya39.Ci-XA_C5bGgRDC3UaD-h0_NeL-DVIQnI2gHtBBBHkZzrwlARkwX6R3O0PCDEzRlfaQ",
// 	 "token_type": "Bearer",
// 	 "expires_in": 3600,
// 	 "refresh_token": "1/r_2c_7jddspcdfesrrfKqfXtqo08D6Q-gUU0DsdfVMsx0c"
// 	}
// 
Chilkat.JsonObject json = new Chilkat.JsonObject();
success = json.LoadFile("qa_data/tokens/_gmailFullAccess.json");
if (success != true) {
    Debug.WriteLine("Failed to load GMail access token file.");
    return;
}

string accessToken = json.StringOf("access_token");

// Do OAuth2 authentication by using the access token as the password in the Login method below...
Chilkat.Imap imap = new Chilkat.Imap();

imap.Ssl = true;
imap.Port = 993;

// Connect to the GMail IMAP server.
success = imap.Connect("imap.gmail.com");
if (success != true) {
    Debug.WriteLine(imap.LastErrorText);
    return;
}

// Indicate that XOAUTH2 authentication is to be used:
imap.AuthMethod = "XOAUTH2";

// Login
// Use the email address of the GMail account that granted authorization.
success = imap.Login("user@gmail.com",accessToken);
if (success != true) {
    Debug.WriteLine(imap.LastErrorText);
}
else {
    Debug.WriteLine("Successfully authenticated with GMail IMAP using XOAUTH2!");
}