Access the Security System in Code

• Mar 28, 2019
• 2 minutes to read

This lesson will guide you through using the static SecuritySystem class to check whether or not a user has particular permission. The SetTask Action will be accessible to users who have permission to modify DemoTask objects.

 

Note

Before proceeding, we recommend that you review the following lessons.

• Using the Security System
• Add an Action with Option Selection

• Open the TaskActionsController.cs (TaskActionsController.vb) file you created in the Add an Action with Option Selection lesson. Add the “using” directive and modify the Activated event handler as shown below.

  C#

  using DevExpress.ExpressApp.Security;
  //...
  public partial class TaskActionsController : ViewController {
      // ...
      private void TaskActionsController_Activated(object sender, EventArgs e) {
          View.SelectionChanged += new EventHandler(View_SelectionChanged);
          UpdateSetTaskActionState();
      }
      void View_SelectionChanged(object sender, EventArgs e) {
          UpdateSetTaskActionState();
      }
      private void UpdateSetTaskActionState() {
          bool isGranted = true;
          foreach(object selectedObject in View.SelectedObjects) {
              bool isPriorityGranted = SecuritySystem.IsGranted(new PermissionRequest(ObjectSpace, 
              typeof(DemoTask), SecurityOperations.Write, selectedObject, "Priority"));
              bool isStatusGranted = SecuritySystem.IsGranted(new PermissionRequest(ObjectSpace, 
              typeof(DemoTask), SecurityOperations.Write, selectedObject, "Status"));
              if(!isPriorityGranted || !isStatusGranted) {
                  isGranted = false;
              }
          }
          SetTaskAction.Enabled.SetItemValue("SecurityAllowance", isGranted);
      }
  }
  

  VB.NET

  Imports DevExpress.ExpressApp.Security
  '...
  Partial Public Class TaskActionsController
      Inherits ViewController
      ' ...
      Private Sub TaskActionsController_Activated(ByVal sender As Object, ByVal e As EventArgs)
          AddHandler View.SelectionChanged, AddressOf View_SelectionChanged
          UpdateSetTaskActionState()
      End Sub
      Private Sub View_SelectionChanged(ByVal sender As Object, ByVal e As EventArgs)
          UpdateSetTaskActionState()
      End Sub
      Private Sub UpdateSetTaskActionState()
          Dim isGranted As Boolean = True
          For Each selectedObject As Object In View.SelectedObjects
              Dim isPriorityGranted As Boolean = SecuritySystem.IsGranted(_
              New PermissionRequest(ObjectSpace, GetType(DemoTask), SecurityOperations.Write, selectedObject, "Priority"))
              Dim isStatusGranted As Boolean = SecuritySystem.IsGranted(_
              New PermissionRequest(ObjectSpace, GetType(DemoTask), SecurityOperations.Write, selectedObject, "Status"))
              If (Not isPriorityGranted) OrElse (Not isStatusGranted) Then
                  isGranted = False
              End If
          Next selectedObject
          SetTaskAction.Enabled.SetItemValue("SecurityAllowance", isGranted)
      End Sub
  End Class
  

  With the added code, the Set Task Action will be activated for users who have write permissions for the Priority and Status properties of the selected DemoTask objects.

• Add a user who does not have permission to modify the DemoTask objects (see Using the Security System). Run the application as this new user. The Set Task Action will not be visible when you display the Demo Task List View.

 

This is the last lesson of the Comprehensive Tutorial. To learn more about the main concepts for building business applications and extending XAF tools, refer to the Concepts section. If you need task-based help, take a look at the Task-Based Help section. To learn how to deploy XAF applications, review the Deployment Tutorial.