public GanttExtension Bind(
    object taskObject,
    object taskDependencyObject,
    object resourceObject,
    object resourceAssignmentObject
)

Public Function Bind(
    taskObject As Object,
    taskDependencyObject As Object,
    resourceObject As Object,
    resourceAssignmentObject As Object
) As GanttExtension

@Html.DevExpress().Gantt(settings => {
    settings.Name = "gantt";
    // ...

    settings.Mappings.Task.Key = "ID";
    settings.Mappings.Task.ParentKey = "ParentID";
    settings.Mappings.Task.Title = "Subject";
    settings.Mappings.Task.Start = "StartDate";
    settings.Mappings.Task.End = "EndDate";
    settings.Mappings.Task.Progress = "PercentComplete";

    settings.Mappings.Dependency.Key = "ID";
    settings.Mappings.Dependency.PredecessorKey = "ParentID";
    settings.Mappings.Dependency.SuccessorKey = "DependentID";
    settings.Mappings.Dependency.DependencyType = "Type";

    settings.Mappings.Resource.Key = "ID";
    settings.Mappings.Resource.Name = "Name";

    settings.Mappings.ResourceAssignment.Key = "ID";
    settings.Mappings.ResourceAssignment.TaskKey = "TaskID";
    settings.Mappings.ResourceAssignment.ResourceKey = "ResourceID";

}).Bind(
    GanttDataProvider.Tasks, 
    GanttDataProvider.Dependencies, 
    GanttDataProvider.Resources, 
    GanttDataProvider.ResourceAssignments
  ).GetHtml()

public static class GanttDataProvider {
    const string
        TasksSessionKey = "Tasks",
        DependenciesSessionKey = "Dependencies",
        ResourcesSessionKey = "Resources",
        ResourceAssignmentsSessionKey = "ResourceAssignments";

    static HttpSessionState Session { get { return HttpContext.Current.Session; } }

    public static List<Task> Tasks {
        get {
            if(Session[TasksSessionKey] == null)
                Session[TasksSessionKey] = CreateTasks();
            return (List<Task>)Session[TasksSessionKey];
        }
    }
    public static List<Dependency> Dependencies {
        get {
            if(Session[DependenciesSessionKey] == null)
                Session[DependenciesSessionKey] = CreateDependencies();
            return (List<Dependency>)Session[DependenciesSessionKey];
        }
    }
    public static List<Resource> Resources {
        get {
            if(Session[ResourcesSessionKey] == null)
                Session[ResourcesSessionKey] = CreateResources();
            return (List<Resource>)Session[ResourcesSessionKey];
        }
    }
    public static List<ResourceAssignment> ResourceAssignments {
        get {
            if(Session[ResourceAssignmentsSessionKey] == null)
                Session[ResourceAssignmentsSessionKey] = CreateResourceAssignments();
            return (List<ResourceAssignment>)Session[ResourceAssignmentsSessionKey];
        }
    }

    static List<Task> CreateTasks() {
        //...
    }

    static List<Dependency> CreateDependencies() {
        //...
    }

    static List<Resource> CreateResources() {
        //...
    }
    static List<ResourceAssignment> CreateResourceAssignments() {
        //...
    }
}