Exception.InnerException Properti

Definisi

Ruang nama:

System

Rakitan:

netstandard.dll, System.Runtime.dll

Sumber:

Exception.cs

Mendapatkan instans Exception yang menyebabkan pengecualian saat ini.

public:
 property Exception ^ InnerException { Exception ^ get(); };

public Exception? InnerException { get; }

member this.InnerException : Exception

Public ReadOnly Property InnerException As Exception

Nilai Properti

Exception

Objek yang menjelaskan kesalahan yang menyebabkan pengecualian saat ini. Properti InnerException mengembalikan nilai yang sama seperti yang diteruskan ke Exception(String, Exception) konstruktor, atau null jika nilai pengecualian dalam tidak diberikan ke konstruktor. Properti ini hanya dapat dibaca.

Contoh

Contoh berikut menunjukkan pelemparan dan penangkapan pengecualian yang mereferensikan pengecualian dalam.

using System;

public class AppException : Exception
{
   public AppException(String message) : base (message)
   {}

   public AppException(String message, Exception inner) : base(message,inner) {}
}

public class Example
{
   public static void Main()
   {
      Example ex = new Example();

      try {
         ex.CatchInner();
      }
      catch(AppException e) {
         Console.WriteLine ("In catch block of Main method.");
         Console.WriteLine("Caught: {0}", e.Message);
         if (e.InnerException != null)
            Console.WriteLine("Inner exception: {0}", e.InnerException);
      }
   }

   public void ThrowInner ()
   {
      throw new AppException("Exception in ThrowInner method.");
   }

   public void CatchInner()
   {
      try {
         this.ThrowInner();
      }
      catch (AppException e) {
         throw new AppException("Error in CatchInner caused by calling the ThrowInner method.", e);
      }
   }
}
// The example displays the following output:
//    In catch block of Main method.
//    Caught: Error in CatchInner caused by calling the ThrowInner method.
//    Inner exception: AppException: Exception in ThrowInner method.
//       at Example.ThrowInner()
//       at Example.CatchInner()

open System

type AppException =
    inherit Exception
    
    new (message: string) = { inherit Exception(message) }

    new (message: string, inner) = { inherit Exception(message, inner) }

let throwInner () =
    raise (AppException "Exception in throwInner function.")
    ()

let catchInner () =
    try
        throwInner ()
    with :? AppException as e ->
        raise (AppException("Error in catchInner caused by calling the throwInner function.", e) )

[<EntryPoint>]
let main _ =
    try
        catchInner ()
    with :? AppException as e ->
        printfn "In with block of main function."
        printfn $"Caught: {e.Message}"
        if e.InnerException <> null then
            printfn $"Inner exception: {e.InnerException}"
    0
// The example displays the following output:
//    In with block of main function.
//    Caught: Error in catchInner caused by calling the throwInner function.
//    Inner exception: Example+AppException: Exception in throwInner function.
//       at Example.throwInner()
//       at Example.catchInner()

Public Class AppException : Inherits Exception
   Public Sub New(message As String)
      MyBase.New(message)
   End Sub
   
   Public Sub New(message As String, inner As Exception)
      MyBase.New(message, inner)
   End Sub
End Class

Public Class Example
   Public Shared Sub Main()
      Dim testInstance As New Example()
      Try
         testInstance.CatchInner()
      Catch e As AppException
         Console.WriteLine ("In catch block of Main method.")
         Console.WriteLine("Caught: {0}", e.Message)
         If e.InnerException IsNot Nothing Then
            Console.WriteLine("Inner exception: {0}", e.InnerException)
         End If
      End Try
   End Sub
   
   Public Sub ThrowInner()
      Throw New AppException("Exception in ThrowInner method.")
   End Sub
   
   Public Sub CatchInner()
      Try
         Me.ThrowInner()
      Catch e As AppException
         Throw New AppException("Error in CatchInner caused by calling the ThrowInner method.", e)
      End Try
   End Sub
End Class
' The example displays the following output:
'    In catch block of Main method.
'    Caught: Error in CatchInner caused by calling the ThrowInner method.
'    Inner exception: AppException: Exception in ThrowInner method.
'       at Example.ThrowInner()
'       at Example.CatchInner()

Keterangan

Ketika pengecualian X dilemparkan sebagai hasil langsung dari pengecualian Ysebelumnya, InnerException properti X harus berisi referensi ke Y.

InnerException Gunakan properti untuk mendapatkan serangkaian pengecualian yang mengarah ke pengecualian saat ini.

Anda dapat membuat pengecualian baru yang menangkap pengecualian sebelumnya. Kode yang menangani pengecualian kedua dapat menggunakan informasi tambahan dari pengecualian sebelumnya untuk menangani kesalahan dengan lebih tepat.

Misalkan ada fungsi yang membaca file dan memformat data dari file tersebut. Dalam contoh ini, karena kode mencoba membaca file, sebuah IOException dilemparkan. Fungsi ini menangkap IOException dan melempar FileNotFoundException. IOException dapat disimpan di InnerException properti FileNotFoundException, memungkinkan kode yang menangkap FileNotFoundException untuk memeriksa penyebab kesalahan awal.

Properti InnerException , yang menyimpan referensi ke pengecualian dalam, diatur pada inisialisasi objek pengecualian.