Call Stack

[Jim Heavey]

My application abends when I press a tab on the tab control. I have tried
to trace what is happening, but is never shows me the line of code which is
failing, I only get a message box telling me I have a null pointer
exception.

I understand that I can use the "Call Trace Stack" tab in the debugger to
"trace" the sequence of events, but I am not able to follow how this will
lead me to the problem. My stack trace has the following entries...

System.Windows.Form.dll!Windows.Forms.Control::Set VisibilityCore(bool
value=true) + 0x207 bytes

System.Windows.Form.dll!Windows.Forms.Control::set _Visible(bool value=true)
+ 0x1e bytes

System.Windows.Form.dll!Windows.Forms.TabPage::set _Visible(bool value=true)
+ 0x1c

So how does this help me find the problem?

Your assistance is greatly appricated!!!!!!!

[Ben Rush]

So, you're following the app in the debugger line by line and this gets
thrown? What function does it get thrown on?
"Jim Heavey" <Ji*******@nospam.com> wrote in message
news:Xn*********************************@207.46.24 8.16...

My application abends when I press a tab on the tab control. I have tried
to trace what is happening, but is never shows me the line of code which is failing, I only get a message box telling me I have a null pointer
exception.

I understand that I can use the "Call Trace Stack" tab in the debugger to
"trace" the sequence of events, but I am not able to follow how this will
lead me to the problem. My stack trace has the following entries...

System.Windows.Form.dll!Windows.Forms.Control::Set VisibilityCore(bool
value=true) + 0x207 bytes

System.Windows.Form.dll!Windows.Forms.Control::set _Visible(bool value=true) + 0x1e bytes

System.Windows.Form.dll!Windows.Forms.TabPage::set _Visible(bool value=true) + 0x1c

So how does this help me find the problem?

Your assistance is greatly appricated!!!!!!!

[Shawn B.]

In the IDE, click the "Debug" menu, click the "Exceptions" item, then click
on the either the "Common Runtime Exceptions" and then choose the "Break
into Debugger" option, or, expand the "Common Runtim Exception" and find
where the null pointer is ?System.NullPointerEcxception? and then choose
"Break Into Debugger" for that item. Run in Debug mode and when that
exception is encountered it'll break on the offending line.
Thanks,
Shawn

"Jim Heavey" <Ji*******@nospam.com> wrote in message
news:Xn*********************************@207.46.24 8.16...

My application abends when I press a tab on the tab control. I have tried
to trace what is happening, but is never shows me the line of code which is failing, I only get a message box telling me I have a null pointer
exception.

I understand that I can use the "Call Trace Stack" tab in the debugger to
"trace" the sequence of events, but I am not able to follow how this will
lead me to the problem. My stack trace has the following entries...

System.Windows.Form.dll!Windows.Forms.Control::Set VisibilityCore(bool
value=true) + 0x207 bytes

System.Windows.Form.dll!Windows.Forms.Control::set _Visible(bool value=true) + 0x1e bytes

System.Windows.Form.dll!Windows.Forms.TabPage::set _Visible(bool value=true) + 0x1c

So how does this help me find the problem?

Your assistance is greatly appricated!!!!!!!

[Stu Smith]

I've always wondered why they're all set to 'continue' by default.... it's
not obvious that you need to turn them on, and debugging is rather difficult
if you can't trace exceptions.
"Shawn B." <le****@html.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

In the IDE, click the "Debug" menu, click the "Exceptions" item, then click on the either the "Common Runtime Exceptions" and then choose the "Break
into Debugger" option, or, expand the "Common Runtim Exception" and find
where the null pointer is ?System.NullPointerEcxception? and then choose
"Break Into Debugger" for that item. Run in Debug mode and when that
exception is encountered it'll break on the offending line.
Thanks,
Shawn

"Jim Heavey" <Ji*******@nospam.com> wrote in message
news:Xn*********************************@207.46.24 8.16...

My application abends when I press a tab on the tab control. I have tried to trace what is happening, but is never shows me the line of code which

is

failing, I only get a message box telling me I have a null pointer
exception.

I understand that I can use the "Call Trace Stack" tab in the debugger to "trace" the sequence of events, but I am not able to follow how this will lead me to the problem. My stack trace has the following entries...

System.Windows.Form.dll!Windows.Forms.Control::Set VisibilityCore(bool
value=true) + 0x207 bytes

System.Windows.Form.dll!Windows.Forms.Control::set _Visible(bool

value=true)

+ 0x1e bytes

System.Windows.Form.dll!Windows.Forms.TabPage::set _Visible(bool

value=true)

+ 0x1c

So how does this help me find the problem?

Your assistance is greatly appricated!!!!!!!