Listbox SelectedIndex set to -1

[Greg Larsen]

I populate an unbound ListBox on a WebForm with the following C# code.

SqlDataReader oDr = sqlCommandGetTa bleList.Execute Reader();
ListBoxTableNam e.DataSource = oDr;
ListBoxTableNam e.DataValueFiel d = "TABLE_NAME ";
ListBoxTableNam e.DataBind();

But when the WebForm is displayed and I highlight a TABLE_NAME in the
listbox the ListBoxTableNam e_SelectedIndex Changed method fires, but the
SelectedIndex value is -1. What am I doing wrong?

[Peter Bromberg [C# MVP]]

Are you closing your SqlDataReader and / or the underlying SqlConnection?
Peter

--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com


"Greg Larsen" wrote:

I populate an unbound ListBox on a WebForm with the following C# code.

SqlDataReader oDr = sqlCommandGetTa bleList.Execute Reader();
ListBoxTableNam e.DataSource = oDr;
ListBoxTableNam e.DataValueFiel d = "TABLE_NAME ";
ListBoxTableNam e.DataBind();

But when the WebForm is displayed and I highlight a TABLE_NAME in the
listbox the ListBoxTableNam e_SelectedIndex Changed method fires, but the
SelectedIndex value is -1. What am I doing wrong?

[Greg Larsen]

No.

I fixed the problem by changing my code to read like this:

sqlConnectionTa bleList.Open();
SqlDataReader oDr = sqlCommandGetTa bleList.Execute Reader();
ListBoxTableNam e.DataSource = oDr;
ListBoxTableNam e.DataValueFiel d = "TABLE_NAME ";
if (!IsPostBack)
{
ListBoxTableNam e.DataBind();
}


"Peter Bromberg [C# MVP]" wrote:

Are you closing your SqlDataReader and / or the underlying SqlConnection?
Peter

--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com


"Greg Larsen" wrote:

I populate an unbound ListBox on a WebForm with the following C# code.

SqlDataReader oDr = sqlCommandGetTa bleList.Execute Reader();
ListBoxTableNam e.DataSource = oDr;
ListBoxTableNam e.DataValueFiel d = "TABLE_NAME ";
ListBoxTableNam e.DataBind();

But when the WebForm is displayed and I highlight a TABLE_NAME in the
listbox the ListBoxTableNam e_SelectedIndex Changed method fires, but the
SelectedIndex value is -1. What am I doing wrong?

[Peter Bromberg [C# MVP]]

good, but you still need to CLOSE your DataReader when you are done, because
it holds the connection open. You can use CommandBehavior .CloseConnectio n
overload, and the closing of the reader will also close the connection.
Peter

--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com


"Greg Larsen" wrote:

No.

I fixed the problem by changing my code to read like this:

sqlConnectionTa bleList.Open();
SqlDataReader oDr = sqlCommandGetTa bleList.Execute Reader();
ListBoxTableNam e.DataSource = oDr;
ListBoxTableNam e.DataValueFiel d = "TABLE_NAME ";
if (!IsPostBack)
{
ListBoxTableNam e.DataBind();
}


"Peter Bromberg [C# MVP]" wrote:

Are you closing your SqlDataReader and / or the underlying SqlConnection?
Peter

--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com


"Greg Larsen" wrote:

I populate an unbound ListBox on a WebForm with the following C# code.
>
SqlDataReader oDr = sqlCommandGetTa bleList.Execute Reader();
ListBoxTableNam e.DataSource = oDr;
ListBoxTableNam e.DataValueFiel d = "TABLE_NAME ";
ListBoxTableNam e.DataBind();
>
But when the WebForm is displayed and I highlight a TABLE_NAME in the
listbox the ListBoxTableNam e_SelectedIndex Changed method fires, but the
SelectedIndex value is -1. What am I doing wrong?
>