iterating through control array

[inzo21]

Hello all,

 

I have the following situation. I have a user control embedded in a web form that has a panel on it. Within the panel, there are other multiple user controls with their initial visibility set to false. When the user clicks on a link in the web form, I want it to set the visibility to true for a prticular user control in the panel. This works fine.

 

However, what I wanted to do is loop through all controls in the panel when the user clicks the linkbutton and set their visibility to off. I then locate the user control in question and set its visbility to on. This is where I'm having an issue. Here is the code I am using in the linkbutton, which is on the user control on the web form.

 

Dim myuc As UserControl = New UserControl

For Each myuc In Me.Controls

myuc.Visible = False

Next myuc

myuc = Me.FindControl("ucsub_x22release")

myuc.Visible = True

 

The error I get is this:

 

Exception Details: System.InvalidCastException: Specified cast is not valid.

 

Source Error:

 

 

Line 57: Private Sub lnk_contactnds_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lnk_contactnds.Click

Line 58: Dim myuc As UserControl = New UserControl

Line 59: For Each myuc In Me.Controls

Line 60: myuc.Visible = False

Line 61: Next myuc

 

 

Source File: C:\Inetpub\wwwroot\xweb\corpinfo.ascx.vb Line: 59

 

Can anyone point me in the right direction on how to accomplish this?

 

Thanx in advance,

 

inzo

[PlausiblyDamp]

Try something like

Dim myuc As UserControl    'you may be better using the correct control type here.
dim c as control
For Each c In Me.Controls
if typeof c is UserControl then
myuc.Visible = False
end if
Next 
myuc = Me.FindControl("ucsub_x22release")
myuc.Visible = True

 

also could you not just put the controls within a panel and change the panel's visibility rather than each control individually.

[modularbeing]

this reminded of something i was doing with validartion of control in a user control. what i was doing was iterating through the control collection to change the backcolor property of those control which are invalid. Well I have about 10 usercontrols each with this same sub in it to do this function. I was wondering if it was possible to move the sub to a single location and pass it the control collection. Any clue as to if this might work by moving it to a single location or should I just keep it in each usercontrol?

[Mothra]

...also could you not just put the controls within a panel and change the panel's visibility rather than each control individually.

 

That is how I usually do it. The problem you run into is that the controls in Me.Controls does not look at nested controls (e.g. a textbox on a panel). In this example, the panel is "seen" but not the textbox inside it.

[PlausiblyDamp]

In that case you could just use a recursive function to find controls nested inside other controls.

 

http://www.xtremedotnettalk.com/showthread.php?t=76358

[Mothra]

Yea, I know but, it was much easier just putting them on a panel and then setting the panels .Visible proprty to false...