Exception.HelpLink Property (System) (original) (raw)
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Exception.HelpLink Property
- Reference
Definition
Gets or sets a link to the help file associated with this exception.
public:
virtual property System::String ^ HelpLink { System::String ^ get(); void set(System::String ^ value); };
public virtual string HelpLink { get; set; }
public virtual string? HelpLink { get; set; }
member this.HelpLink : string with get, set
Public Overridable Property HelpLink As String
Property Value
The Uniform Resource Name (URN) or Uniform Resource Locator (URL).
Implements
Examples
The following code example throws an Exception
that sets the HelpLink
property in its constructor and then catches the exception and displays HelpLink
.
// Example for the Exception::HelpLink, Exception::Source,
// Exception::StackTrace, and Exception::TargetSite properties.
using namespace System;
namespace NDP_UE_CPP
{
// Derive an exception; the constructor sets the HelpLink and
// Source properties.
public ref class LogTableOverflowException: public Exception
{
private:
static String^ overflowMessage = "The log table has overflowed.";
public:
LogTableOverflowException( String^ auxMessage, Exception^ inner )
: Exception( String::Format( "{0} - {1}", overflowMessage, auxMessage ), inner )
{
this->HelpLink = "https://learn.microsoft.com";
this->Source = "Exception_Class_Samples";
}
};
public ref class LogTable
{
public:
LogTable( int numElements )
{
logArea = gcnew array<String^>(numElements);
elemInUse = 0;
}
protected:
array<String^>^logArea;
int elemInUse;
public:
// The AddRecord method throws a derived exception if
// the array bounds exception is caught.
int AddRecord( String^ newRecord )
{
try
{
logArea[ elemInUse ] = newRecord;
return elemInUse++;
}
catch ( Exception^ ex )
{
throw gcnew LogTableOverflowException( String::Format( "Record \"{0}\" was not logged.", newRecord ),ex );
}
}
};
// Create a log table and force an overflow.
void ForceOverflow()
{
LogTable^ log = gcnew LogTable( 4 );
try
{
for ( int count = 1; ; count++ )
{
log->AddRecord( String::Format( "Log record number {0}", count ) );
}
}
catch ( Exception^ ex )
{
Console::WriteLine( "\nMessage ---\n{0}", ex->Message );
Console::WriteLine( "\nHelpLink ---\n{0}", ex->HelpLink );
Console::WriteLine( "\nSource ---\n{0}", ex->Source );
Console::WriteLine( "\nStackTrace ---\n{0}", ex->StackTrace );
Console::WriteLine( "\nTargetSite ---\n{0}", ex->TargetSite->ToString() );
}
}
}
int main()
{
Console::WriteLine( "This example of \n Exception::Message, \n"
" Exception::HelpLink, \n Exception::Source, \n"
" Exception::StackTrace, and \n Exception::"
"TargetSite \ngenerates the following output." );
NDP_UE_CPP::ForceOverflow();
}
/*
This example of
Exception::Message,
Exception::HelpLink,
Exception::Source,
Exception::StackTrace, and
Exception::TargetSite
generates the following output.
Message ---
The log table has overflowed. - Record "Log record number 5" was not logged.
HelpLink ---
https://learn.microsoft.com
Source ---
Exception_Class_Samples
StackTrace ---
at NDP_UE_CPP.LogTable.AddRecord(String newRecord)
at NDP_UE_CPP.ForceOverflow()
TargetSite ---
Int32 AddRecord(System.String)
*/
// Example for the Exception.HelpLink, Exception.Source,
// Exception.StackTrace, and Exception.TargetSite properties.
using System;
namespace NDP_UE_CS
{
// Derive an exception; the constructor sets the HelpLink and
// Source properties.
class LogTableOverflowException : Exception
{
const string overflowMessage = "The log table has overflowed.";
public LogTableOverflowException(
string auxMessage, Exception inner ) :
base( String.Format( "{0} - {1}",
overflowMessage, auxMessage ), inner )
{
this.HelpLink = "https://learn.microsoft.com";
this.Source = "Exception_Class_Samples";
}
}
class LogTable
{
public LogTable( int numElements )
{
logArea = new string[ numElements ];
elemInUse = 0;
}
protected string[ ] logArea;
protected int elemInUse;
// The AddRecord method throws a derived exception if
// the array bounds exception is caught.
public int AddRecord( string newRecord )
{
try
{
logArea[ elemInUse ] = newRecord;
return elemInUse++;
}
catch( Exception e )
{
throw new LogTableOverflowException(
String.Format( "Record \"{0}\" was not logged.",
newRecord ), e );
}
}
}
class OverflowDemo
{
// Create a log table and force an overflow.
public static void Main()
{
LogTable log = new LogTable( 4 );
Console.WriteLine(
"This example of \n Exception.Message, \n" +
" Exception.HelpLink, \n Exception.Source, \n" +
" Exception.StackTrace, and \n Exception." +
"TargetSite \ngenerates the following output." );
try
{
for( int count = 1; ; count++ )
{
log.AddRecord(
String.Format(
"Log record number {0}", count ) );
}
}
catch( Exception ex )
{
Console.WriteLine( "\nMessage ---\n{0}", ex.Message );
Console.WriteLine(
"\nHelpLink ---\n{0}", ex.HelpLink );
Console.WriteLine( "\nSource ---\n{0}", ex.Source );
Console.WriteLine(
"\nStackTrace ---\n{0}", ex.StackTrace );
Console.WriteLine(
"\nTargetSite ---\n{0}", ex.TargetSite );
}
}
}
}
/*
This example of
Exception.Message,
Exception.HelpLink,
Exception.Source,
Exception.StackTrace, and
Exception.TargetSite
generates the following output.
Message ---
The log table has overflowed. - Record "Log record number 5" was not logged.
HelpLink ---
https://learn.microsoft.com
Source ---
Exception_Class_Samples
StackTrace ---
at NDP_UE_CS.LogTable.AddRecord(String newRecord)
at NDP_UE_CS.OverflowDemo.Main()
TargetSite ---
Int32 AddRecord(System.String)
*/
// Example for the Exception.HelpLink, Exception.Source,
// Exception.StackTrace, and Exception.TargetSite properties.
open System
let overflowMessage = "The log table has overflowed."
// Derive an exception; the constructor sets the HelpLink and
// Source properties.
type LogTableOverflowException(auxMessage, inner) as this =
inherit Exception($"%s{overflowMessage} - %s{auxMessage}", inner)
do
this.HelpLink <- "https://learn.microsoft.com"
this.Source <- "Exception_Class_Samples"
type LogTable(numElements) =
let logArea = Array.zeroCreate<string> numElements
let mutable elemInUse = 0
// The AddRecord method throws a derived exception if
// the array bounds exception is caught.
member this.AddRecord(newRecord) =
try
logArea[elemInUse] <- newRecord
elemInUse <- elemInUse + 1
elemInUse - 1
with e ->
raise (LogTableOverflowException($"Record \"{newRecord}\" was not logged.", e) )
// Create a log table and force an overflow.
let log = LogTable 4
printfn
"""This example of
Exception.Message,
Exception.HelpLink,
Exception.Source,
Exception.StackTrace, and
Exception.TargetSite
generates the following output."""
try
for count = 1 to 1000000 do
log.AddRecord $"Log record number {count}"
|> ignore
with ex ->
printfn $"\nMessage ---\n{ex.Message}"
printfn $"\nHelpLink ---\n{ex.HelpLink}"
printfn $"\nSource ---\n{ex.Source}"
printfn $"\nStackTrace ---\n{ex.StackTrace}"
printfn $"\nTargetSite ---\n{ex.TargetSite}"
// This example of
// Exception.Message,
// Exception.HelpLink,
// Exception.Source,
// Exception.StackTrace, and
// Exception.TargetSite
// generates the following output.
// Message ---
// The log table has overflowed. - Record "Log record number 5" was not logged.
// HelpLink ---
// https://learn.microsoft.com
// Source ---
// Exception_Class_Samples
// StackTrace ---
// at NDP_UE_FS.LogTable.AddRecord(String newRecord)
// at <StartupCode$fs>.$NDP_UE_FS.main@()
// TargetSite ---
// Int32 AddRecord(System.String)
' Example for the Exception.HelpLink, Exception.Source,
' Exception.StackTrace, and Exception.TargetSite properties.
Namespace NDP_UE_VB
' Derive an exception; the constructor sets the HelpLink and
' Source properties.
Class LogTableOverflowException
Inherits Exception
Private Const overflowMessage As String = _
"The log table has overflowed."
Public Sub New( auxMessage As String, inner As Exception )
MyBase.New( String.Format( "{0} - {1}", _
overflowMessage, auxMessage ), inner )
Me.HelpLink = "https://learn.microsoft.com"
Me.Source = "Exception_Class_Samples"
End Sub
End Class
Class LogTable
Public Sub New(numElements As Integer)
logArea = New String(numElements) {}
elemInUse = 0
End Sub
Protected logArea() As String
Protected elemInUse As Integer
' The AddRecord method throws a derived exception if
' the array bounds exception is caught.
Public Function AddRecord( newRecord As String ) As Integer
Try
Dim curElement as Integer = elemInUse
logArea( elemInUse ) = newRecord
elemInUse += 1
Return curElement
Catch ex As Exception
Throw New LogTableOverflowException( _
String.Format( "Record ""{0}"" was not logged.", _
newRecord ), ex )
End Try
End Function ' AddRecord
End Class
Module OverflowDemo
' Create a log table and force an overflow.
Sub Main( )
Dim log As New LogTable( 4 )
Console.WriteLine( "This example of " & vbCrLf & _
" Exception.Message, " & vbCrLf & _
" Exception.HelpLink, " & vbCrLf & _
" Exception.Source, " & vbCrLf & _
" Exception.StackTrace, and " & vbCrLf & _
" Exception.TargetSite " & vbCrLf & _
"generates the following output." )
Try
Dim count As Integer = 0
Do
log.AddRecord( _
String.Format( "Log record number {0}", count ) )
count += 1
Loop
Catch ex As Exception
Console.WriteLine( vbCrLf & _
"Message ---" & vbCrLf & ex.Message )
Console.WriteLine( vbCrLf & _
"HelpLink ---" & vbCrLf & ex.HelpLink )
Console.WriteLine( vbCrLf & _
"Source ---" & vbCrLf & ex.Source )
Console.WriteLine( vbCrLf & _
"StackTrace ---" & vbCrLf & ex.StackTrace )
Console.WriteLine( vbCrLf & "TargetSite ---" & _
vbCrLf & ex.TargetSite.ToString( ) )
End Try
End Sub
End Module ' OverflowDemo
End Namespace ' NDP_UE_VB
' This example of
' Exception.Message,
' Exception.HelpLink,
' Exception.Source,
' Exception.StackTrace, and
' Exception.TargetSite
' generates the following output.
'
' Message ---
' The log table has overflowed. - Record "Log record number 5" was not logged.
'
' HelpLink ---
' https://learn.microsoft.com
'
' Source ---
' Exception_Class_Samples
'
' StackTrace ---
' at NDP_UE_VB.LogTable.AddRecord(String newRecord)
' at NDP_UE_VB.OverflowDemo.Main()
'
' TargetSite ---
' Int32 AddRecord(System.String)
Remarks
The return value, which represents a help file, is a URN or URL. For example, the HelpLink
value could be:
"file:///C:/Applications/Bazzal/help.html#ErrorNum42"
Applies to
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