Exception.HResult Egenskap

Definition

Hämtar eller anger HRESULT, ett kodat numeriskt värde som har tilldelats ett specifikt undantag.

public:  property int HResult {  public:
int get(); protected:
 void set(int value); };
protected:
 property int HResult { int get(); void set(int value); };
public int HResult { get; protected set; }
protected int HResult { get; set; }
member this.HResult : int with get, set
Public Property HResult As Integer
Protected Property HResult As Integer

Egenskapsvärde

HRESULT-värdet.

Exempel

I följande kodexempel definieras en härledd Exception klass som anger HResult egenskapen till ett anpassat värde i konstruktorn.

// Example for the Exception.HResult property.
using System;

namespace NDP_UE_CS
{
    // Create the derived exception class.
    class SecondLevelException : Exception
    {
        const int SecondLevelHResult = unchecked( (int)0x81234567 );

        // Set HResult for this exception, and include it in
        // the exception message.
        public SecondLevelException( string message, Exception inner ) :
            base( string.Format( "(HRESULT:0x{1:X8}) {0}",
                message, SecondLevelHResult ), inner )
        {
            HResult = SecondLevelHResult;
        }
    }

    class HResultDemo
    {
        public static void Main()
        {
            // This function forces a division by 0 and throws
            // a second exception.
            try
            {
                try
                {
                    int  zero = 0;
                    int  ecks = 1 / zero;
                }
                catch( Exception ex )
                {
                    throw new SecondLevelException(
                        "Forced a division by 0 and threw " +
                        "a second exception.", ex );
                }
            }
            catch( Exception ex )
            {
                Console.WriteLine( ex.ToString( ) );
            }
        }
    }
}

/*
This example of Exception.HResult generates the following output.

NDP_UE_CS.SecondLevelException: (HRESULT:0x81234567) Forced a division by 0 and
 threw a second exception. ---> System.DivideByZeroException: Attempted to divi
de by zero.
   at NDP_UE_CS.HResultDemo.Main()
   --- End of inner exception stack trace ---
   at NDP_UE_CS.HResultDemo.Main()
*/
// Example for the Exception.HResult property.
open System

let secondLevelHResult = 0x81234567

// Create the derived exception class.
// Set HResult for this exception, and include it in the exception message.
type SecondLevelException(message, inner) as this =
    inherit Exception($"(HRESULT:0x{secondLevelHResult:X8}) %s{message}", inner)
    do
        this.HResult <- secondLevelHResult

// The following forces a division by 0 and throws a second exception.
try
    try
        let zero = 0
        let ecks = 1 / zero
        ()
    with ex ->
        raise (SecondLevelException("Forced a division by 0 and threw a second exception.", ex) )
with ex ->
    printfn $"{ex}"

// This example of Exception.HResult generates the following output.
//
// NDP_UE_FS+SecondLevelException: (HRESULT:0x81234567) Forced a division by 0 and
//  threw a second exception. ---> System.DivideByZeroException: Attempted to divi
// de by zero.
//    at <StartupCode$fs>.$NDP_UE_FS.main@()
//    --- End of inner exception stack trace ---
//    at <StartupCode$fs>.$NDP_UE_FS.main@()
' Example for the Exception.HResult property.
Namespace NDP_UE_VB

    ' Create the derived exception class.
    Class SecondLevelException
        Inherits Exception

        Private Const SecondLevelHResult As Integer = &H81234567
       
        ' Set HResult for this exception, and include it in 
        ' the exception message.
        Public Sub New(message As String, inner As Exception)

            MyBase.New( String.Format( "(HRESULT:0x{1:X8}) {0}", _
                message, SecondLevelHResult ), inner )
            HResult = SecondLevelHResult
        End Sub
    End Class

    Module HResultDemo
       
        Sub Main()
            ' This function forces a division by 0 and throws 
            ' a second exception.
            Try
                Try
                    Dim zero As Integer = 0
                    Dim ecks As Integer = 1 \ zero

                Catch ex As Exception
                    Throw New SecondLevelException( _
                        "Forced a division by 0 and threw " & _
                        "a second exception.", ex )
                End Try
              
            Catch ex As Exception
                Console.WriteLine( ex.ToString( ) )
            End Try
        End Sub

    End Module ' HResultDemo
End Namespace ' NDP_UE_VB

' This example of Exception.HResult generates the following output.
' 
' NDP_UE_VB.SecondLevelException: (HRESULT:0x81234567) Forced a division by 0 a
' nd threw a second exception. ---> System.DivideByZeroException: Attempted to
' divide by zero.
'    at NDP_UE_VB.HResultDemo.Main()
'    --- End of inner exception stack trace ---
'    at NDP_UE_VB.HResultDemo.Main()

Kommentarer

HRESULT är ett 32-bitarsvärde, indelat i tre olika fält: en allvarlighetsgradskod, en anläggningskod och en felkod. Allvarlighetsgradskoden anger om returvärdet representerar information, varning eller fel. Anläggningskoden identifierar det område i systemet som är ansvarigt för felet. Felkoden är ett unikt nummer som har tilldelats för att representera undantaget. Varje undantag mappas till en distinkt HRESULT. När hanterad kod utlöser ett undantag skickar körningen HRESULT till COM-klienten. När ohanterad kod returnerar ett fel konverteras HRESULT till ett undantag som sedan genereras av körningen. Information om HRESULT-värden och deras motsvarande .NET Framework-undantag finns i How to: Map HRESULTs and Exceptions. Se Common HRESULT-värden i dokumentationen för Windows för en lista över de värden som du mest sannolikt kommer att stöta på.

Från och med .NET Framework 4.5 skyddas HResult egenskapens setter, medan dess getter är offentlig. I tidigare versioner av .NET Framework skyddas både getter och setter.

Gäller för

Se även