The Railing line must be a single connected Sketch. If you want separate pieces of Railing, create two or more separate Railings.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 26.2.0.0 (26.2.0.0)
Syntax
C#
public static FailureDefinitionId RailingNotConnected { get; }