Question

I want to set the selecteditem attribute for an ASP.Net dropdownlist control programmatically.

So I want to pass a value to the dropdownlist control to set the selected item where the item is equal to the passed value.

Answer 1

Assuming the list is already data bound you can simply set the SelectedValue property on your dropdown list.

list.DataSource = GetListItems(); // <-- Get your data from somewhere.
list.DataValueField = "ValueProperty";
list.DataTextField = "TextProperty";
list.DataBind();

list.SelectedValue = myValue.ToString();

The value of the myValue variable would need to exist in the property specified within the DataValueField in your controls databinding.

UPDATE:
If the value of myValue doesn’t exist as a value with the dropdown list options it will default to select the first option in the dropdown list.