未连接时处理 AD 错误

Question

我正在使用下面的代码来获取 logge don 用户的登录名。这在连接到网络/域时工作正常。但是当离线时，我在第 3 行得到一个错误：

PrincipalServerDownException 未处理

无法联系到服务器。

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Dim currentADUser As System.DirectoryServices.AccountManagement.UserPrincipal
    currentADUser = System.DirectoryServices.AccountManagement.UserPrincipal.Current
    Dim DisplayName As String = currentADUser.GivenName & " " & currentADUser.Surname
    Label5.Text = DisplayName
    Label4.Text = GetUserProperties()
End Sub

我怎样才能检查它，并向用户返回一个有用的错误，例如“不在网络上”或“未连接到域”，然后退出？我已经尝试了以下方法，但这只是给出了同样的错误：

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Dim currentADUser As System.DirectoryServices.AccountManagement.UserPrincipal
    If System.DirectoryServices.AccountManagement.UserPrincipal.Current Is Nothing Then
        MsgBox("Network Error: No Connection to Domain")
        Application.Exit()
    Else ....
    End if
End Sub

Answer 1

使用 try/catch

    Try
        Dim currentADUser As System.DirectoryServices.AccountManagement.UserPrincipal
        currentADUser = System.DirectoryServices.AccountManagement.UserPrincipal.Current
        Dim DisplayName As String = currentADUser.GivenName & " " & currentADUser.Surname
        Label5.Text = DisplayName
        Label4.Text = GetUserProperties()
    Catch ex As Exception
        MsgBox(...)
    End Try