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V25.1
  • RegistryAccessPolicy.QueryValue Event

    Fires when the DevExpress control attempts to read a value from a system registry key and allows you to cancel the operation.

    Namespace: DevExpress.Data.Utils

    Assembly: DevExpress.Data.Desktop.v25.1.dll

    NuGet Packages: DevExpress.Data.Desktop, DevExpress.ExpressApp.Win.Design

    #Declaration

    public static event EventHandler<RegistryAccessPolicy.ValueEventArgs> QueryValue

    #Event Data

    The QueryValue event's data class is RegistryAccessPolicy.ValueEventArgs. The following properties provide information specific to this event:

    Property Description
    Cancel Gets or sets a value indicating whether the event should be canceled. Inherited from CancelEventArgs.
    Hive Gets a registry hive (a logical group of keys, subkeys, and values in the registry). Inherited from RegistryAccessPolicy.RegistryOperationBaseEventArgs.
    Key Gets the requested registry key. Inherited from RegistryAccessPolicy.RegistryOperationBaseEventArgs.
    Name Gets the name of the value stored in a registry key.
    Operation Gets an operation on a key value in the system registry.

    #Remarks

    Set the e.Cancel event parameter to true to cancel the operation. e.Hive, e.Key, and e.Name event parameters identify a registry hive, key, and name respectively.

    The following example suppresses attempts to read values from the specified system registry path:

    static string privatePath = "SPECIFY_REGISTRY_PRIVATE_PATH";
    static void Main() {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        DevExpress.Data.Utils.RegistryAccessPolicy.QueryValue += RegistryAccessPolicy_QueryValue;
        Application.Run(new Form1());
    }
    static void RegistryAccessPolicy_QueryValue(object sender, DevExpress.Data.Utils.RegistryAccessPolicy.ValueEventArgs e) {
      e.Cancel = e.Key.Contains(privatePath);
    }
    

    Read the following topic for additional information: Registry Access Policy.

    See Also