Setting SelectedIndex -1 ASP.NET DropDownList - asp.net

Question

Is there a way to select -1 index without adding a new ListItem("", "-1",true)) from code behind like jQuery does?
Here is an example:
http://jsfiddle.net/eL8sn/

Answer 1

If you're binding it on Page_Load event it does a post back (AutoPostBack='True').It will simply rebind ever time the index is changed
if (!IsPostBack)
{
BindDropDownList1();
}
(or)
If the above solution dosen't work try to add an empty item as shown:
this.myDropDownList.Items.Add(new ListItem("Select...", ""));

Answer 2

Do you mean like this?
DropDownList1.SelectedIndex = -1;
That's how one usually does it from code-behind.
ETA: I now see what you are talking about. And I'm afraid I don't see how it can be done from server side. All you can do on the server side is control the rendering. As far as I can tell, even if you render this code:
<select id="testSelect" selectedIndex="-1">
... it still appears with the top option appearing to be selected.
It looks as if only by explicitly setting it to -1 with javascript after rendering will it appear with absolutely nothing selected. It appears as if it can't be done declaratively in HTML.
If you can find a way to write the tag in HTML so that it appears this way on load, then you could tweak the rendering in code-behind (using .AddAttribute() or similar) but if it can't be done with a declaration, it'll need javascript.
(You could of course write a jQuery snippet to change all your dropdowns to selectedIndex = -1, but you'll have thought of that!)

Answer 3

You can do this
string selectStr = "SELECT";
string allStr = "ALL"
ListItem allLI = new ListItem(allStr,allStr);
ListItem selectLI = new ListItem(selectStr,selectStr);
DropDownList.Items.Add(selectLI);
DropDownList.Items.Add(allLI);
//code to fill the DropDownList with the list that your query returns
DropDownList.SelectedValue = selectStr;