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ConnectivityStatus Class

  • Reference

Definition

Namespace:
System.Web.ClientServices
Assembly:
System.Web.Extensions.dll

Represents the status of an application's network connection.

public ref class ConnectivityStatus abstract sealed
public static class ConnectivityStatus
type ConnectivityStatus = class
Public Class ConnectivityStatus
Inheritance
Object
ConnectivityStatus

Examples

The following example code demonstrates how to use this class to update the offline status depending on a check box value. In this example, a CheckedChanged event handler updates the offline status. If the user sets the application to the online state, the event handler attempts to revalidate the user. However, if the authentication server is unavailable, the event handler returns the application to the offline state.

private void workOfflineCheckBox_CheckedChanged(
    object sender, EventArgs e)
{
    ConnectivityStatus.IsOffline = workOfflineCheckBox.Checked;
    if (!ConnectivityStatus.IsOffline)
    {
        try
        {
            // Silently re-validate the user.
            ((ClientFormsIdentity)
                System.Threading.Thread.CurrentPrincipal.Identity)
                .RevalidateUser();

            // If any settings have been changed locally, save the new
            // new values to the Web settings service.
            SaveSettings();

            // If any settings have not been changed locally, check 
            // the Web settings service for updates. 
            Properties.Settings.Default.Reload();
        }
        catch (System.Net.WebException)
        {
            MessageBox.Show(
                "Unable to access the authentication service. " +
                Environment.NewLine + "Staying in offline mode.",
                "Warning", MessageBoxButtons.OK, 
                MessageBoxIcon.Warning);
            workOfflineCheckBox.Checked = true;
        }
    }
}

Private Sub workOfflineCheckBox_CheckedChanged( _
    ByVal sender As Object, ByVal e As EventArgs) _
    Handles workOfflineCheckBox.CheckedChanged

    ConnectivityStatus.IsOffline = workOfflineCheckBox.Checked
    If Not ConnectivityStatus.IsOffline Then

        Try

            ' Silently re-validate the user.
            CType(System.Threading.Thread.CurrentPrincipal.Identity,  _
                ClientFormsIdentity).RevalidateUser()

            ' If any settings have been changed locally, save the new
            ' new values to the Web settings service.
            SaveSettings()

            ' If any settings have not been changed locally, check 
            ' the Web settings service for updates. 
            My.Settings.Reload()

        Catch ex As System.Net.WebException

            MessageBox.Show( _
                "Unable to access the authentication service. " & _
                Environment.NewLine + "Staying in offline mode.", _
                "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning)
            workOfflineCheckBox.Checked = True

        End Try

    End If
End Sub

Remarks

Use the ConnectivityStatus class to specify the network connectivity of Windows-based applications that use client application services. When you set the IsOffline property to true, the client service providers use the offline cache instead of attempting to access the corresponding Web services. The offline status is stored on a per-user and per-application basis. For more information, see How to: Work Offline with Client Application Services.

Properties

IsOffline

Gets or sets a value indicating whether an application is in offline mode.

Applies to

See also