This will be useful if we were given with one of the dropdown list item and we were asked to make the given item as the selected content of the dropdownlist.In this case,we will find the index of the item and then bind that index with the dropdown.In this way,we will be able to make the given text as the selected item of the dropdown list.

DropDownList.SelectedIndex=DropDownList.Items.Inde xOf(DropDownList.Items.FindByText(string));
DropDownList.Databind();