HResult Property

Exception.HResult Property


Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

Public Property HResult As Integer
	Protected Set
End Property

Property Value

Type: System.Int32

The HRESULT value.

HRESULT is a 32-bit value, divided into three different fields: a severity code, a facility code, and an error code. The severity code indicates whether the return value represents information, warning, or error. The facility code identifies the area of the system responsible for the error. The error code is a unique number that is assigned to represent the exception. Each exception is mapped to a distinct HRESULT. When managed code throws an exception, the runtime passes the HRESULT to the COM client. When unmanaged code returns an error, the HRESULT is converted to an exception, which is then thrown by the runtime. For information about HRESULT values and their corresponding .NET Framework exceptions, see How to: Map HRESULTs and Exceptions. See Common HRESULT Values in the Windows documentation for a list of the values you are most likely to encounter.

Starting with the .NET Framework 4.5, the HResult property's setter is protected, whereas its getter is public. In previous versions of the .NET Framework, both getter and setter are protected.

The following code example defines a derived Exception class that sets the HResult property to a custom value in its constructor.

' Example for the Exception.HResult property.
Imports System
Imports Microsoft.VisualBasic

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 ' New
    End Class ' SecondLevelException

    Module HResultDemo

        Sub Main()
            Console.WriteLine( _
                "This example of Exception.HResult " & _
                "generates the following output." & vbCrLf )

            ' This function forces a division by 0 and throws 
            ' a second exception.
                    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 ' Main

    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()

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Return to top
© 2015 Microsoft