DropDownList Bind

Question

public void dropdownlist()

{

string qry = "select * from dept_detail";

SqlDataAdapter sda = new SqlDataAdapter(qry, ConfigurationManager.ConnectionStrings["cn"].ConnectionString);

DataSet ds = new DataSet();

DropDownList2.DataSource = ds;

DropDownList2.DataTextField = "deptname";

DropDownList2.DataValueField = "deptno";

DropDownList2.DataBind();

}

 

Hello, I have a simple questions dropdownlist bind error.

The error is "The iListSource does not contain any data sources"

Connection string - Verified.

Database & Tabel - Verified

Please help me