How to insert blank item in Telerik OpenAccessLinqDataSource programmatically?

[Prasad]

I am using Telerik OpenAccessLinqDataSource. I have loaded the records into that and assign its id to dropdownlist. Its working fine. But, now I want to add blank item into it. How can I insert blank item to Telerik OpenAccessLinqDataSource programmatically and pass it to dropdownlist?

[Doroteya]

Hi Prasad,

To achieve the necessary behavior you  can use the DataBound event of RadDropDownList and in it to add a blank item without inserting it to the datasource at all. For example:

ASPX

<telerik:RadDropDownList runat="server" ID="rDropDownList"
    DataSourceID="oaLinqDataSource" DataTextField="PropertyToDisplay" DataValueField="IDProperty"
    DropDownHeight="200" EnableVirtualScrolling="true"
    OnDataBound="rDropDownList_DataBound">
</telerik:RadDropDownList>

C#

protected void rDropDownList_DataBound(object sender, EventArgs e)
{
    this.rDropDownList.Items.Insert(0, new Telerik.Web.UI.DropDownListItem());
    this.rDropDownList.SelectedIndex = 0;
}

This way after you retrieve the records through the datasource and bind the result to the control, at the top of the list you will have a blank item.

I hope this helps. If you have additional questions, do not hesitate to get back to us.



Regards,
Doroteya
Telerik