XSOM - Authentication via SharePoint REST API for С# + Helper classes

Wrapper Library for SharePoint REST operations

Projects:

• XSOM - Wrapper library for SharePoint REST
• XSOM WinForms Sample - sample for debugging purposes

Tested with SharePoint Online and SharePoint Online + ADFS

In SharePoint Online tenants where Legacy authentication is disabled, we won't be able to authenticate by passing login and password in clear text. How to check if legacy authentication is enabled:

Connect-SPOService -Url https://contoso-admin.sharepoint.com
$tenant = Get-SPOTenant
$tenant.LegacyAuthProtocolsEnabled

How to enable legacy authentication:

Connect-SPOService -Url –https://<tenant>-admin.sharepoint.com
Set-SPOTenant –LegacyAuthProtocolsEnabled $true

Note: legacy authentication is considered unsafe.