Error - Cannot modify the items collection...

[Guest]

Hello
I already posted this question, but received no response
I'll try to word it better :

I have a form with a lisbox (LBox1), a button, that when pressed populates LBox1, and a tab control with 2 pages
On the 2nd tab page is another listbox (LBox2), whose values are based on what is selected in LBox1
If I run the project, and go directly to the 2nd tab page, then populate LBox1, everything works great
If I populate LBox1 first, then click on the 2nd tab page, I get the error message
"An unhandled exception of type 'System.ArgumentException' occurred in system.windows.forms.dl
Additional information: Cannot modify the Items collection when the DataSource property is set.

The code that triggers the error is in the following sub

Private Sub get_all_CBs(
lBox2.datasource = Nothin
lBox2.items.Clear(
lBox2.Refresh(

Dim DI2 as String = txtCPID.Tex
Dim ConStr2 as String = "...my connection string...
Dim dsACB as DataSet = SqlHelper.ExecuteDataset(ConStr2, CommandType.Text, ...my SQL code...
lBox2.DataSource = dsACB.Tables(0) <<----- this is the line that triggers the error..
lBox2.DisplayMember = "STR_BLOCK_NUMBER

Please help!!

Thanks in advance
Ambe

 

[Cor]

Hi Amber,

I do not see it, but try this

Private Sub get_all_CBs()
lBox2.datasource = Nothing
lBox2.items.Clear()
lBox2.Refresh()

Delete the three rows above

Dim DI2 as String = txtCPID.Text
Dim ConStr2 as String = "...my connection string..."
Dim dsACB as DataSet = SqlHelper.ExecuteDataset(ConStr2,

CommandType.Text, ...my SQL code...)

Lbox2.datasource = Nothing ' and not more

lBox2.DataSource = dsACB.Tables(0) <<----- this is the line that triggers the error...
lBox2.DisplayMember = "STR_BLOCK_NUMBER"

Cor

 

[Guest]

Thanks for the reply
This may sound bizarre, but at first it seemed to work, then after trying it a few times...it started giving me the error message again
I'm truly baffled here...
ambe

 

[Cor]

Amber

Are you sure you are not trying to add an item in that listbox somewhere
else?

Cor