Hello:
I have a aspx web page - let's call it main.aspx
It contains a placeholder: Myplaceholder.
I have a web control, lets call it webcontrol which has a code behind class
called webcontrolclass and a label called mycontrollabel
In the webcontrolclass , I have a private sub called:
Sub writetomycontro llabel(stuff as text)
mycontrollabel. text=stuff
End Sub
The code behind main.aspx
Dim MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx") ' needed for
the placeholder
Public MyMANAGEGENERAL As New webcontrolclass
I have a sub which is called by a button located on main.aspx
Sub mainaspx_click( usualstuff ) handles mainaspx.Click
MyPlaceholder.C ontrols.Add(MAN AGEGENERAL)
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
End sub
I get the error message:
Object reference not set to an instance of an object.
Exception Details: System.NullRefe renceException: Object reference not set
to an instance of an object.
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
So, I am missing something obvious - but I dont get it.
Help
Thanks
Terry
4  1204 
I think you need to load the control using
LoadControl method and then add it to the controls collection. The
problem is that the label control inside your custom control is not
loaded yet..
hth
-ashish
ote: Hello:
I have a aspx web page - let's call it main.aspx
It contains a placeholder: Myplaceholder.
I have a web control, lets call it webcontrol which has a code behind class
called webcontrolclass and a label called mycontrollabel
In the webcontrolclass , I have a private sub called:
Sub writetomycontro llabel(stuff as text)
mycontrollabel. text=stuff
End Sub
The code behind main.aspx
Dim MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx") ' needed for
the placeholder
Public MyMANAGEGENERAL As New webcontrolclass
I have a sub which is called by a button located on main.aspx
Sub mainaspx_click( usualstuff ) handles mainaspx.Click
MyPlaceholder.C ontrols.Add(MAN AGEGENERAL)
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
End sub
I get the error message:
Object reference not set to an instance of an object.
Exception Details: System.NullRefe renceException: Object reference not set
to an instance of an object.
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
So, I am missing something obvious - but I dont get it.
Help
Thanks
Terry
Where does
MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx")
exist? In Page_Load? Is it executed with every postback and before the
Click event?
--
Scott http://www.OdeToCode.com/blogs/scott/
On Tue, 22 Mar 2005 16:15:15 -0500, "Support"
<Re************ ****@mail.oci.s tate.ga.us> wrote: Hello:
I have a aspx web page - let's call it main.aspx
It contains a placeholder: Myplaceholder.
I have a web control, lets call it webcontrol which has a code behind class
called webcontrolclass and a label called mycontrollabel
In the webcontrolclass , I have a private sub called:
Sub writetomycontro llabel(stuff as text)
mycontrollabel. text=stuff
End Sub
The code behind main.aspx
Dim MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx") ' needed for
the placeholder
Public MyMANAGEGENERAL As New webcontrolclass
I have a sub which is called by a button located on main.aspx
Sub mainaspx_click( usualstuff ) handles mainaspx.Click
MyPlaceholder. Controls.Add(MA NAGEGENERAL)
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
End sub
I get the error message:
Object reference not set to an instance of an object.
Exception Details: System.NullRefe renceException: Object reference not set
to an instance of an object.
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
So, I am missing something obvious - but I dont get it.
Help
Thanks
Terry
exist before and page Loads ...
Public Class A
Inherits System.Web.UI.P age
Dim MANAGEGENERAL As Control = LoadControl("Ma nageGeneral.asc x")
Private Sub PAge_Init() Handles MyBAse.Init
End Sub
Private Sub PAge_Load() Handles MyBase.Load
MyPlaceholder.C ontrols.Add(MAN AGEGENERAL)
End Sub
Terry
"Scott Allen" <sc***@nospam.o detocode.com> wrote in message
news:bo******** *************** *********@4ax.c om... Where does
MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx")
exist? In Page_Load? Is it executed with every postback and before the
Click event?
--
Scott
http://www.OdeToCode.com/blogs/scott/
On Tue, 22 Mar 2005 16:15:15 -0500, "Support"
<Re************ ****@mail.oci.s tate.ga.us> wrote:
Hello:
I have a aspx web page - let's call it main.aspx
It contains a placeholder: Myplaceholder.
I have a web control, lets call it webcontrol which has a code behind
class
called webcontrolclass and a label called mycontrollabel
In the webcontrolclass , I have a private sub called:
Sub writetomycontro llabel(stuff as text)
mycontrollabel. text=stuff
End Sub
The code behind main.aspx
Dim MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx") ' needed for
the placeholder
Public MyMANAGEGENERAL As New webcontrolclass
I have a sub which is called by a button located on main.aspx
Sub mainaspx_click( usualstuff ) handles mainaspx.Click
MyPlaceholder .Controls.Add(M ANAGEGENERAL)
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
End sub
I get the error message:
Object reference not set to an instance of an object.
Exception Details: System.NullRefe renceException: Object reference not set
to an instance of an object.
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
So, I am missing something obvious - but I dont get it.
Help
Thanks
Terry
You might want to turn on two options under Project -> Properties ->
Build: Option Strict and Option Explicit. That might help track down
the source of the error, looking at the code it doesn't seem these
options are on.
--
Scott http://www.OdeToCode.com/blogs/scott/
On Thu, 24 Mar 2005 07:40:45 -0500, "Support"
<Re************ ****@mail.oci.s tate.ga.us> wrote: exist before and page Loads ...
Public Class A
Inherits System.Web.UI.P age
Dim MANAGEGENERAL As Control = LoadControl("Ma nageGeneral.asc x")
Private Sub PAge_Init() Handles MyBAse.Init
End Sub
Private Sub PAge_Load() Handles MyBase.Load
MyPlaceholder.C ontrols.Add(MAN AGEGENERAL)
End Sub
Terry
"Scott Allen" <sc***@nospam.o detocode.com> wrote in message
news:bo******* *************** **********@4ax. com... Where does
MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx")
exist? In Page_Load? Is it executed with every postback and before the
Click event?
--
Scott
http://www.OdeToCode.com/blogs/scott/
On Tue, 22 Mar 2005 16:15:15 -0500, "Support"
<Re************ ****@mail.oci.s tate.ga.us> wrote:
Hello:
I have a aspx web page - let's call it main.aspx
It contains a placeholder: Myplaceholder.
I have a web control, lets call it webcontrol which has a code behind
class
called webcontrolclass and a label called mycontrollabel
In the webcontrolclass , I have a private sub called:
Sub writetomycontro llabel(stuff as text)
mycontrollabel. text=stuff
End Sub
The code behind main.aspx
Dim MANAGEGENERAL As Control = LoadControl("we bcontrol.ascx") ' needed for
the placeholder
Public MyMANAGEGENERAL As New webcontrolclass
I have a sub which is called by a button located on main.aspx
Sub mainaspx_click( usualstuff ) handles mainaspx.Click
MyPlaceholde r.Controls.Add( MANAGEGENERAL)
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
End sub
I get the error message:
Object reference not set to an instance of an object.
Exception Details: System.NullRefe renceException: Object reference not set
to an instance of an object.
MyMANAGEGENERAL .writetomycontr ollabel("hello" )
So, I am missing something obvious - but I dont get it.
Help
Thanks
Terry
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