How to add default value to DropDownList control

First, we will bind data source to drop down list.  Set the segment as below.

 

           ddlCatalogName.DataSource = dtCatalogIDs;
           ddlCatalogName.DataTextField = "CatalogName";
           ddlCatalogName.DataValueField = "CatalogID";
           ddlCatalogName.DataBind();

 

Then add a default value to this drop down list such as "Please select".

           // Add default value
           ddlCatalogName.Items.Insert(0, new ListItem("------Select------", "0"));

 

Ok. That's all.