Asp.net - Add blank item at top of dropdownlist

Question

Why is the dropdown not showing my blank item first? Here is what I have

drpList.Items.Add(New ListItem(\"\", \"\"))

With drpList
    .DataSource = myContro         


        

Answer 1

The databinding takes place after you've added your blank list item, and it replaces what's there already, you need to add the blank item to the beginning of the List from your controller, or add it after databinding.

EDIT:

After googling this quickly as of ASP.Net 2.0 there's an "AppendDataBoundItems" true property that you can set to...append the databound items.

for details see

http://imar.spaanjaars.com/QuickDocId.aspx?quickdoc=281 or

http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.listcontrol.appenddatabounditems.aspx

Answer 2

After your databind:

drpList.Items.Insert(0, new ListItem(String.Empty, String.Empty));
drpList.SelectedIndex = 0;

Answer 3

Do your databinding and then add the following:

Dim liFirst As New ListItem("", "")
drpList.Items.Insert(0, liFirst)

Answer 4

it looks like you are adding a blank item, and then databinding, which would empty the list; try inserting the blank item after databinding

Answer 5

You could also have a union of the blank select with the select that has content:

select '' value, '' name
union
select value, name from mytable

Answer 6

I think a better way is to insert the blank item first, then bind the data just as you have been doing. However you need to set the AppendDataBoundItems property of the list control.

We use the following method to bind any data source to any list control...

public static void BindList(ListControl list, IEnumerable datasource, string valueName, string textName)
{
    list.Items.Clear();
    list.Items.Add("", "");
    list.AppendDataBoundItems = true;
    list.DataValueField = valueName;
    list.DataTextField = textName;
    list.DataSource = datasource;
    list.DataBind();
}