Best practice for Error Handling in ASP.Net and C#

[RonL]

What is the recommended best technique for handling errors/exceptions in
ASP.Net. I've read about the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in the glabal.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about the
pros and cons of #2 and #3.

Thanks,
Ron

[Juan T. Llibre]

See :

http://msdn.microsoft.com/library/de...Exceptions.asp

http://msdn.microsoft.com/library/de...ceptdotnet.asp

http://www.c-sharpcorner.com/Code/20...Management.asp


Juan T. Llibre, asp.net MVP
aspnetfaq.com : http://www.aspnetfaq.com/
asp.net faq : http://asp.net.do/faq/
foros de asp.net, en español : http://asp.net.do/foros/
=============== =============== =====
"RonL" <ro***@hotmail. com> wrote in message news:NV******** ***********@new ssvr29.news.pro digy.net...

What is the recommended best technique for handling errors/exceptions in ASP.Net. I've read about
the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in global.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about the pros and cons of #2 and
#3.

Thanks,
Ron

[Peter Bromberg [C# MVP]]

Use try/ catch /finally semantics anywhere in your code that an exception
could possibly occur.

Use a global Application_Err or implementation to take care of unhandled
exceptions.

Write your code defensively so that you take every effort NOT to have an
exception.

Peter
--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com


"RonL" wrote:

What is the recommended best technique for handling errors/exceptions in
ASP.Net. I've read about the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in the glabal.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about the
pros and cons of #2 and #3.

Thanks,
Ron

[RonL]

Thanks for the response. Combining Try/Catch with Application_Err or sounds
good. I'm working on an "in development" application inherited from an
acquired company. I have a question about Application_Err or, does one have
access to the Response object so as to redirect to an error screen?

Thanks,
Ron

"Peter Bromberg [C# MVP]" <pb*******@yaho o.nospammin.com > wrote in message
news:A7******** *************** ***********@mic rosoft.com...

Use try/ catch /finally semantics anywhere in your code that an exception
could possibly occur.

Use a global Application_Err or implementation to take care of unhandled
exceptions.

Write your code defensively so that you take every effort NOT to have an
exception.

Peter
--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com


"RonL" wrote:

What is the recommended best technique for handling errors/exceptions in
ASP.Net. I've read about the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in the glabal.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about the
pros and cons of #2 and #3.

Thanks,
Ron

[RonL]

Thanks for the links. I noticed one of the links it talked about using
reflection to retrieve the data from Exception object. Have you seen any
examples on how to do that?

Thanks,
Ron

"Juan T. Llibre" <no***********@ nowhere.com> wrote in message
news:OB******** ******@TK2MSFTN GP14.phx.gbl...

See :

http://msdn.microsoft.com/library/de...Exceptions.asp

http://msdn.microsoft.com/library/de...ceptdotnet.asp

http://www.c-sharpcorner.com/Code/20...Management.asp


Juan T. Llibre, asp.net MVP
aspnetfaq.com : http://www.aspnetfaq.com/
asp.net faq : http://asp.net.do/faq/
foros de asp.net, en español : http://asp.net.do/foros/
=============== =============== =====
"RonL" <ro***@hotmail. com> wrote in message
news:NV******** ***********@new ssvr29.news.pro digy.net...

What is the recommended best technique for handling errors/exceptions in
ASP.Net. I've read about
the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in global.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about the
pros and cons of #2 and
#3.

Thanks,
Ron

[Kevin Spencer]

Hi Ron,

Have you seen any examples on how to do that?
Here's a function I wrote for our applications, which I use in conjunction
with an error-handling utility. Remarks follow:

private static void GetExceptionDet ails(Exception ex, ref StringBuilder sb)
{
int i;
sb.Append(sb.Le ngth == 0 ? "" : nl);
Type t = ex.GetType();
Type[] types = new Type[] {
typeof(WebExcep tion),
typeof(SqlExcep tion),
typeof(SmtpExce ption),
typeof(SmtpFail edRecipientExce ption),
typeof(SmtpFail edRecipientsExc eption),
typeof(Configur ationException) ,
typeof(FileNotF oundException),
typeof(Protocol ViolationExcept ion)
};

string TypeName = t.ToString();

// Get type of Exception
for (i = 0; i < types.Length; i++)
{
if (t.Equals(types[i]))
break;
}
sb.Append("Exce ption of Type \"" + TypeName + "\"" + nl);

// Handle with the appropriate handler
switch (i)
{
case 0: // WebException
GetWebException ((WebException) ex, ref sb);
break;
case 1: // SqlException
GetSqlException ((SqlException) ex, ref sb);
break;
case 2: // SmtpException
GetSmtpExceptio n((SmtpExceptio n)ex, ref sb);
break;
case 3: // SmtpFailedRecip ientException
GetSmtpFailedRe cipientExceptio n(
(SmtpFailedReci pientException) ex, ref sb);
break;
case 4: // SmtpFailedRecip ientsException
GetSmtpFailedRe cipientsExcepti on(
(SmtpFailedReci pientsException )ex, ref sb);
break;
case 5: // System.Configur ation.Configura tionException
GetConfiguratio nException(
(ConfigurationE xception)ex, ref sb);
break;
case 6:
GetFileNotFound Exception(
(FileNotFoundEx ception)ex, ref sb);
break;
case 7:
GetProtocolViol ationException(
(ProtocolViolat ionException)ex , ref sb);
break;
default:
GetSystemExcept ion(ex, ref sb);
break;
}
if (ex.Data != null && ex.Data.Count > 0)
{
sb.Append(nl + "Data:");
foreach (DictionaryEntr y d in ex.Data)
sb.Append(nl + "Key: " + d.Key.ToString( ) +
", Value: " + d.Value.ToStrin g());
}

if (ex.InnerExcept ion != null)
{
sb.Append(nl + "InnerException : " + nl);
GetExceptionDet ails(ex.InnerEx ception, ref sb);
}
sb.Append(nl + "StackTrace : " + nl + ex.StackTrace);
if (ex.HelpLink != null && ex.HelpLink != "")
sb.Append(nl + "HelpLink: " + ex.HelpLink);
}

Basically, this method is passed a Stringbuilder by reference. It then looks
at the type of the Exception, and calls any of several overloads, depending
upon the Exception's type. It then looks at the InnerException, and if any
exists, it calls itself recursively for the InnerException. What it returns
is a Stringbuilder with a formatted string that can be logged in any way.

--
HTH,

Kevin Spencer
Microsoft MVP
Professional Numbskull

Show me your certification without works,
and I'll show my certification
*by* my works.

"RonL" <ro***@hotmail. com> wrote in message
news:av******** ***********@new ssvr12.news.pro digy.com... Thanks for the links. I noticed one of the links it talked about using
reflection to retrieve the data from Exception object. Have you seen any
examples on how to do that?

Thanks,
Ron

"Juan T. Llibre" <no***********@ nowhere.com> wrote in message
news:OB******** ******@TK2MSFTN GP14.phx.gbl...

See :

http://msdn.microsoft.com/library/de...Exceptions.asp

http://msdn.microsoft.com/library/de...ceptdotnet.asp

http://www.c-sharpcorner.com/Code/20...Management.asp


Juan T. Llibre, asp.net MVP
aspnetfaq.com : http://www.aspnetfaq.com/
asp.net faq : http://asp.net.do/faq/
foros de asp.net, en español : http://asp.net.do/foros/
=============== =============== =====
"RonL" <ro***@hotmail. com> wrote in message
news:NV******** ***********@new ssvr29.news.pro digy.net...

What is the recommended best technique for handling errors/exceptions in
ASP.Net. I've read about
the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in global.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about the
pros and cons of #2 and
#3.

Thanks,
Ron

[RonL]

Thanks for the example. I'll check it out.

Ron

"Kevin Spencer" <ke***@DIESPAMM ERSDIEtakempis. com> wrote in message
news:Ow******** ********@TK2MSF TNGP09.phx.gbl. ..

Hi Ron,

Have you seen any examples on how to do that?

Here's a function I wrote for our applications, which I use in conjunction
with an error-handling utility. Remarks follow:

private static void GetExceptionDet ails(Exception ex, ref StringBuilder
sb)
{
int i;
sb.Append(sb.Le ngth == 0 ? "" : nl);
Type t = ex.GetType();
Type[] types = new Type[] {
typeof(WebExcep tion),
typeof(SqlExcep tion),
typeof(SmtpExce ption),
typeof(SmtpFail edRecipientExce ption),
typeof(SmtpFail edRecipientsExc eption),
typeof(Configur ationException) ,
typeof(FileNotF oundException),
typeof(Protocol ViolationExcept ion)
};

string TypeName = t.ToString();

// Get type of Exception
for (i = 0; i < types.Length; i++)
{
if (t.Equals(types[i]))
break;
}
sb.Append("Exce ption of Type \"" + TypeName + "\"" + nl);

// Handle with the appropriate handler
switch (i)
{
case 0: // WebException
GetWebException ((WebException) ex, ref sb);
break;
case 1: // SqlException
GetSqlException ((SqlException) ex, ref sb);
break;
case 2: // SmtpException
GetSmtpExceptio n((SmtpExceptio n)ex, ref sb);
break;
case 3: // SmtpFailedRecip ientException
GetSmtpFailedRe cipientExceptio n(
(SmtpFailedReci pientException) ex, ref sb);
break;
case 4: // SmtpFailedRecip ientsException
GetSmtpFailedRe cipientsExcepti on(
(SmtpFailedReci pientsException )ex, ref sb);
break;
case 5: // System.Configur ation.Configura tionException
GetConfiguratio nException(
(ConfigurationE xception)ex, ref sb);
break;
case 6:
GetFileNotFound Exception(
(FileNotFoundEx ception)ex, ref sb);
break;
case 7:
GetProtocolViol ationException(
(ProtocolViolat ionException)ex , ref sb);
break;
default:
GetSystemExcept ion(ex, ref sb);
break;
}
if (ex.Data != null && ex.Data.Count > 0)
{
sb.Append(nl + "Data:");
foreach (DictionaryEntr y d in ex.Data)
sb.Append(nl + "Key: " + d.Key.ToString( ) +
", Value: " + d.Value.ToStrin g());
}

if (ex.InnerExcept ion != null)
{
sb.Append(nl + "InnerException : " + nl);
GetExceptionDet ails(ex.InnerEx ception, ref sb);
}
sb.Append(nl + "StackTrace : " + nl + ex.StackTrace);
if (ex.HelpLink != null && ex.HelpLink != "")
sb.Append(nl + "HelpLink: " + ex.HelpLink);
}

Basically, this method is passed a Stringbuilder by reference. It then
looks at the type of the Exception, and calls any of several overloads,
depending upon the Exception's type. It then looks at the InnerException,
and if any exists, it calls itself recursively for the InnerException.
What it returns is a Stringbuilder with a formatted string that can be
logged in any way.

--
HTH,

Kevin Spencer
Microsoft MVP
Professional Numbskull

Show me your certification without works,
and I'll show my certification
*by* my works.

"RonL" <ro***@hotmail. com> wrote in message
news:av******** ***********@new ssvr12.news.pro digy.com...

Thanks for the links. I noticed one of the links it talked about using
reflection to retrieve the data from Exception object. Have you seen any
examples on how to do that?

Thanks,
Ron

"Juan T. Llibre" <no***********@ nowhere.com> wrote in message
news:OB******** ******@TK2MSFTN GP14.phx.gbl...

See :

http://msdn.microsoft.com/library/de...Exceptions.asp

http://msdn.microsoft.com/library/de...ceptdotnet.asp

http://www.c-sharpcorner.com/Code/20...Management.asp


Juan T. Llibre, asp.net MVP
aspnetfaq.com : http://www.aspnetfaq.com/
asp.net faq : http://asp.net.do/faq/
foros de asp.net, en español : http://asp.net.do/foros/
=============== =============== =====
"RonL" <ro***@hotmail. com> wrote in message
news:NV******** ***********@new ssvr29.news.pro digy.net...
What is the recommended best technique for handling errors/exceptions
in ASP.Net. I've read about
the following techniques:

1. Try/Catch

2. Page_Error

3. Application_Err or in global.asax

4. Custom errors in Web.Config.
I'm probably going to go with #1 (Try/Catch) but was wondering about
the pros and cons of #2 and
#3.

Thanks,
Ron