[asp.net] Databound drop down list - initial value

How do I set the initial value of a databound drop down list in ASP.NET?

For instance, I want the values, but the first value to display should be -- Select One ---, with a null value.

What I do is set the text property of the drop down list AFTER I databind it. Something like this:

   protected void LoadPersonComboBox()
    {
        var p = new PeopleBLL();

        rcmbboxEditPerson.DataSource = p.GetPeople();
        rcmbboxEditPerson.DataBind();
        rcmbboxEditPerson.Text = "Please select an existing person to edit...";
    }

This makes the initial visible value of this dropdown show up, but not actually be a part of the drop down, nor is it a selectable.

hi friend in this case you can use the

AppendDataBound="true"

and after this use the list item. for e.g.:

<asp:DropDownList ID="DropDownList1" runat="server" AppendDataBoundItems="true">
    <asp:ListItem Text="--Select One--" Value="" />   
</asp:DropDownList>

but the problem in this is after second time select data are append with old data.

To select a value from the dropdown use the index like this:

if we have the

<asp:DropDownList ID="DropDownList1" runat="server" AppendDataBoundItems="true"></asp:DropDownList>

you would use :

DropDownList1.Items[DropDownList1.SelectedIndex].Value

this would return the value for the selected index.

dropdownlist.Items.Insert(0, new Listitem("--Select One--", "0");

I know this is old, but a combination of these ideas leads to a very elegant solution:

Keep all the default property settings for the DropDownList (AppendDataBoundItems=false, Items empty). Then handle the DataBound event like this:

protected void dropdown_DataBound(object sender, EventArgs e)
{
    DropDownList list = sender as DropDownList;
    if (list != null)
        list.Items.Insert(0, "--Select One--");
}

The icing on the cake is that this one handler can be shared by any number of DropDownList objects, or even put into a general-purpose utility library for all your projects.

Add an item and set its "Selected" property to true, you will probably want to set "appenddatabounditems" property to true also so your initial value isn't deleted when databound.

If you are talking about setting an initial value that is in your databound items then hook into your ondatabound event and set which index you want to selected=true you will want to wrap it in "if not page.isPostBack then ...." though

Protected Sub DepartmentDropDownList_DataBound(ByVal sender As Object, ByVal e As    System.EventArgs) Handles DepartmentDropDownList.DataBound
    If Not Page.IsPostBack Then
        DepartmentDropDownList.SelectedValue = "somevalue"
    End If
End Sub

I know this already has a chosen answer - but I wanted to toss in my two cents. I have a databound dropdown list:

<asp:DropDownList 
  id="country" 
  runat="server" 
  CssClass="selectOne" 
  DataSourceID="country_code" 
  DataTextField="Name" 
  DataValueField="CountryCode_PK"
></asp:DropDownList>
<asp:SqlDataSource 
  id="country_code" 
  runat="server" 
  ConnectionString="<%$ ConnectionStrings:DBConnectionString %>"
  SelectCommand="SELECT CountryCode_PK, CountryCode_PK + ' - ' + Name AS N'Name' FROM TBL_Country ORDER BY CountryCode_PK"
></asp:SqlDataSource>

In the codebehind, I have this - (which selects United States by default):

if (this.IsPostBack)
{
  //handle posted data
}
else 
{
  country.SelectedValue = "US";
}

The page initially loads based on the 'US' value rather than trying to worry about a selectedIndex (what if another item is added into the data table - I don't want to have to re-code)