Combobox

[Jim Heavey]

I thought I could create a "ListViewIt em" and then bind that item to a
combox box, but perhaps that is was with an ASP.Net control. When I create
a listViewItem and bind it to a combo box, it does bind, but what show up
is something like ListViewItem{My Field}.

So if I have a hastable, what mechanism would I use to create a bindable
object such that I can define the "ValueMembe r" and "DisplayMember" ?

Thanks in advance for your assistance!!!!! !!!!

[Jan Tielens]

Complex DataBinding accepts as a data source either an IList or an
IListSource. So you can't bind a HashTable directly to a ComboBox.

The following code shows a work-around:
Dim myHashTable as new System.Collecti ons.Hashtable()

myHashTable("GA ") = "Georgia"
myHashTable("FL ") = "Florida"
myHashTable("AL ") = "Alabama"

For each Item in myHashTable
Dim newListItem as new ListItem()
newListItem.Tex t = Item.Value
newListItem.Val ue = Item.Key
DropDownList1.I tems.Add(newLis tItem)
Next

http://www.devcity.net/net/article.a...spnet_dropdown

--
Greetz,
Jan
_______________ _______________ ____
Read my weblog: http://weblogs.asp.net/jan
"Jim Heavey" <Ji*******@nosp am.com> schreef in bericht
news:Xn******** *************** **********@207. 46.248.16...

I thought I could create a "ListViewIt em" and then bind that item to a
combox box, but perhaps that is was with an ASP.Net control. When I create a listViewItem and bind it to a combo box, it does bind, but what show up
is something like ListViewItem{My Field}.

So if I have a hastable, what mechanism would I use to create a bindable
object such that I can define the "ValueMembe r" and "DisplayMember" ?

Thanks in advance for your assistance!!!!! !!!!

[Glen Jones MCSD]

Jim,

The dropdown control can take a ListViewItem object as a parameter to the
Items.Add() method but it only uses the Text property when adding it. The
ListViewItem is only full used by ListBox class.

I'm not sure why you are trying to use binding instead of a loop with calls
the DropDownList.Ad d() method but, keep in mind the nature of binding. All
objects can be bound to most controls, however some controls simply call the
ToString() method if the object does not support the IEnumarable interface.

Simply put the most common use of binding is to set the DataSource property
to a collection or array. Then set the other Data...Field propertys with
the field names. Then when the DataBind() method is called the control loops
through the DataSource object using the IEnumerable interface and uses
reflection to load the control with the Data Fields specified.
Note: Binding is always slower than Adds due to the use of reflection.

With that said, since a Hashtable class supports the IEnumerable interface
you can do the following: Set the DropDownList.Da taSource property to the
Hashtable object, Set the DropDownList.Da taTextField property to "Value" as
in the IDictionaryEnum erator.Value, Set the DropDownList.Da taValueField
property to "Key" as in the IDictionaryEnum erator.Key.

One thing of note is that when loading the Value object, from the Hashtable,
will have it's ToString() method called. This is why when you bound the
ListViewItem, you saw the text you did.

For more information on C# Controls look at the MSDN help and look for the
"DropDownLi st class" and the "Hashtable class" in the index. Each method
and property are described in detail.

A little long winded but hope this helps.
--
Glen Jones MCSD

"Jim Heavey" <Ji*******@nosp am.com> wrote in message
news:Xn******** *************** **********@207. 46.248.16...

I thought I could create a "ListViewIt em" and then bind that item to a
combox box, but perhaps that is was with an ASP.Net control. When I create a listViewItem and bind it to a combo box, it does bind, but what show up
is something like ListViewItem{My Field}.

So if I have a hastable, what mechanism would I use to create a bindable
object such that I can define the "ValueMembe r" and "DisplayMember" ?

Thanks in advance for your assistance!!!!! !!!!