System.Runtime.Versioning.ObsoletedOSPlatformAttribute sealed class ObsoletedOSPlatformAttribute : Attribute Marks APIs that were obsoleted in a given operating system version. Documentation Code public string Message { get; } public string Url { get; set; } public ObsoletedOSPlatformAttribute(string platformName) public ObsoletedOSPlatformAttribute(string platformName, string message)