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C#

SharePoint Rest API using OAuth

See more OAuth2 Examples

Demonstrates how to get an OAuth2 access token for the SharePoint REST API.

Chilkat C# Downloads

C#
bool success = false;

// To further clarify, see OAuth 2.0 Authorization Flow

Chilkat.OAuth2 oauth2 = new Chilkat.OAuth2();

// The ListenPort should match the port in your localhost Reply URL of your Azure AD app.
// Your Reply URL must be exactly "http://localhost:LISTEN_PORT/"
//    * Do not use "https"
//    * Make sure the ending "/" is included.
//    * You may choose any port number that doesn't collide with anything else.
oauth2.ListenPort = 3017;

oauth2.AuthorizationEndpoint = "https://login.microsoftonline.com/TENANT_ID/oauth2/authorize";
oauth2.TokenEndpoint = "https://login.windows.net/TENANT_ID/oauth2/token?api-version=1.0";

// Replace these with actual values.
// Use the application ID
oauth2.ClientId = "CLIENT_ID";
// Use the password
oauth2.ClientSecret = "CLIENT_SECRET";

oauth2.CodeChallenge = false;

oauth2.Scope = "openid";
oauth2.Resource = "https://graph.microsoft.com/";

oauth2.IncludeNonce = true;
oauth2.ResponseMode = "form_post";
oauth2.ResponseType = "id_token+code";

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
string url = oauth2.StartAuth();
if (oauth2.LastMethodSuccess == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

Debug.WriteLine("url = " + url);

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
success = oauth2.LaunchBrowser(url);
if (success == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

// Wait for the user to approve or deny authorization in the browser.
int numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(100);
    numMsWaited = numMsWaited + 100;
}

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response – The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if (oauth2.AuthFlowState < 3) {
    oauth2.Cancel();
    Debug.WriteLine("No response from the browser!");
    return;
}

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if (oauth2.AuthFlowState == 5) {
    Debug.WriteLine("OAuth2 failed to complete.");
    Debug.WriteLine(oauth2.FailureInfo);
    return;
}

if (oauth2.AuthFlowState == 4) {
    Debug.WriteLine("OAuth2 authorization was denied.");
    Debug.WriteLine(oauth2.AccessTokenResponse);
    return;
}

if (oauth2.AuthFlowState != 3) {
    Debug.WriteLine("Unexpected AuthFlowState:" + Convert.ToString(oauth2.AuthFlowState));
    return;
}

Debug.WriteLine("OAuth2 authorization granted!");
Debug.WriteLine("Access Token = " + oauth2.AccessToken);