Another newbie question

  • Thread starter Thread starter RD
  • Start date Start date
R

RD

In vb6 I could add items to a listbox using the add method and the itemdata
property could contain say the primary key of a Sql table (a long in all my
cases)

How do you add items to a listbox in vbnet in code, using a datareader, so
that one property of the listbox displays the string value that you want to
show but there is also stored in another property that which corresponds to
what was the itemdata in vb6 (the primary key of a sql table, long integer
type) that and that can be retrieved? It used to be
Mylistbox.itemdata(MyListBox(selecteditem)

I guess that was too simple ;-)

Thanks for any help,

Bob
 
RD said:
In vb6 I could add items to a listbox using the add method and the
itemdata property could contain say the primary key of a Sql table (a
long in all my cases)

How do you add items to a listbox in vbnet in code, using a
datareader, so that one property of the listbox displays the string
value that you want to show but there is also stored in another
property that which corresponds to what was the itemdata in vb6 (the
primary key of a sql table, long integer type) that and that can be
retrieved? It used to be
Mylistbox.itemdata(MyListBox(selecteditem)

I guess that was too simple ;-)
Click to expand...

Now you are not longer limited to two values (Text+ItemData) per Item. You
can add any object you want. The return values of the objects' ToString
method (every object has a ToString method) is the text displayed in the
listbox. Example:

public class MyItem
public readonly Text as string
public readonly ID as integer

public sub New(Text as string, ID as integer)
me.text = text
me.id = id
end sub

public overrides Function ToString() as string
return me.text
end function
end Class

'...

mylistbox.items.add(new myitem(DR("text"), DR("id")))

'...
To access an item:

dim Item as myitem
item = directcast(mylistbox.items(0), myitem)
msgbox item.text & " " & item.id
 
RD said:
How do you add items to a listbox in vbnet in code,
using a datareader, so that one property of the listbox
displays the string value that you want to show but there
is also stored in another property that which corresponds to
what was the itemdata in vb6 (the primary key of a sql table,
long integer type) that and that can be retrieved? It used to be
Mylistbox.itemdata(MyListBox(selecteditem)
Click to expand...

\\\
Dim p As New Person()
p.Name = "Pink Panther"
p.Age = 22

Me.ComboBox1.Items.Add(p)

MessageBox.Show( _
DirectCast(Me.ComboBox1.Items.Item(0), Person).ToString() _
)
..
..
..
Public Class Person
Private m_strName As Object
Private m_intAge As Integer

Public Property Name() As String
Get
Return m_strName
End Get
Set(ByVal Value As String)
m_strName = Value
End Set
End Property

Public Property Age() As Integer
Get
Return m_intAge
End Get
Set(ByVal Value As Integer)
m_intAge = Value
End Set
End Property

Public Overrides Function ToString() As String
Return m_strName & " (" & m_intAge.ToString() & ")"
End Function
End Class
///
 
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