stuck: I cant reach usercontrol's class ..

24 Mar 2005 1:16 PM

Support

in asp.net
If I have a web usercontrol WUC with code behind Class CLASSWUC
and I have a web page that loads the control

Private Sub Page_Init(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Init
MANAGEGENERAL = LoadControl("WUC.ascx")
MyPlaceholder.Controls.Add(MANAGEGENERAL)
InitializeComponent()
End Sub

And if in CLASSWUC I have a finction that displays a value on the label of
WUC like

Sub DisplayValue(value as String)
    Mylabel.text=value
End Sub

QUESTION:

What code shoud I have in my web page to be able to call DisplayValue so as
to display a value in the label.

I current get the message:
Line 1122:            Dim stuff As New
PORTAL.ManageGeneralNameSpace.CLASSWUC
Line 1123:            stuff.DisplayValue("test")
Exception Details: System.NullReferenceException: Object reference not set
to an instance of an object.

Thanks

1 Apr 2005 6:47 PM

Louis Yeung

Well, I am also green in this usercontrol world. I believe that you should be
able to do so in Page_Init because the instance variable MANAGEGENERAL should
be of class CLASSWUC. Therefore, MANAGEGENERAL.DisplayValue("xxx") is valid.

I do not think "new CLASSWUC" is a good idea because this is a user control
class. It is normally created via "LoadControl". I believe you want to get
back the created CLASSWUC instance rather than using a new instance.

...Louis

Show quote

"Support" wrote:

> in asp.net
> If I have a web usercontrol WUC with code behind Class CLASSWUC
> and I have a web page that loads the control
>
> Private Sub Page_Init(ByVal sender As System.Object, ByVal e As
> System.EventArgs) Handles MyBase.Init
> MANAGEGENERAL = LoadControl("WUC.ascx")
> MyPlaceholder.Controls.Add(MANAGEGENERAL)
> InitializeComponent()
> End Sub
>
> And if in CLASSWUC I have a finction that displays a value on the label of
> WUC like
>
> Sub DisplayValue(value as String)
>     Mylabel.text=value
> End Sub
>
> QUESTION:
>
> What code shoud I have in my web page to be able to call DisplayValue so as
> to display a value in the label.
>
> I current get the message:
> Line 1122:            Dim stuff As New
> PORTAL.ManageGeneralNameSpace.CLASSWUC
> Line 1123:            stuff.DisplayValue("test")
> Exception Details: System.NullReferenceException: Object reference not set
> to an instance of an object.
>
> Thanks
>
>
>