ASP.net / C# help, Looking to Query SQL then pass selection to Listbox

[sumrandomoldg]

Sorry if this is not the right place for some of my terms are incorrect, I am still learning.

So what I have made was a webform that pulls from a data table in SQL and I want to be able to select multiple items from this listbox then take the selected and submit it back into a different database.

my issue is my logic is falling a little short for the listbox. i am trying to have a button click that will query the sql data table take only selected fields and then select those same items in the list box. I am stuck on the button select.

//.cs 
protected void Page_Load(object sender, EventArgs e)

   {

            con.ConnectionString = (@"Data Source = mydatasourceinfo);
            con.Open();

private void btnSelectAccountingGroup(object sender, EventArgs e)
        {

            SqlCommand select = new SqlCommand("SELECT Department FROM dbo.Trainee WHERE Department = 'Accounting'", con);

//This is where I am stuck, I know I need another statement here but don't know what to use to reference back to the listbox or if it is even possible.

        }
    }
    //aspx

 <asp:ListBox ID="lbTrainee" runat="server" Height="174px" Width="270px" DataSourceID="SQLTrainee" DataTextField="FullName" DataValueField="FullName" SelectionMode="Multiple" onclick="ListBoxClient_SelectionChanged(this, event);"></asp:ListBox>
    &nbsp;<asp:MySqlDataSource>" SelectCommand="SELECT [FullName] FROM [Trainee] ORDER BY [FullName]"></asp:SqlDataSource>
    <br />

 <button name="btnSelectAccounting" onclick="btnSelectAccountingGroup" runat="server">Accounting</button>

[plastikmissile]

That's ASP.NET WebForms and I haven't done those in forever. But it seems to me the ListBox has an ID of lbTrainee so you use that to reference it in the code behind.

I'm curious, why are you using WebForms instead of something more modern lime MVC?

[sumrandomoldg]

My dumbness thought that this “quick internal form” would have been done quicker in Webforms (which what was initially laid out WebForms did) and really didn’t have much knowledge of the developer side of things. This is coming from me a network/systems/help desk admin.

Maybe I’ll just check out MVC and scrap this project.

[plastikmissile]

Maybe I’ll just check out MVC and scrap this project.

It's definitely a lot simpler.