https://learn.microsoft.com/en-us/uwp/api/windows.devices.sms.smsencodedlength?view=winrt-28000
SmsEncodedLength Struct (Windows.Devices.Sms) - Windows apps | Microsoft Learn
This structure represents information about the length of an SmsTextMessage object when it is encoded as a PDU. Note This functionality is available only to...
windows devicessms appsstructmicrosoftlearn