C#

SqlConnection conn = new SqlConnection(ConnString);
SqlDataAdapter da = new SqlDataAdapter(query, ConnString);

SqlConnection conn = new SqlConnection(ConnString);
conn.open;
SqlDataAdapter da = new SqlDataAdapter(query, conn);

overloaded Name wrote:

but does not show data either.

if (Page.IsPostBack) return;

Experience is what you get when you didn't get what you wanted. - Randy Pausch

public List<T> MyMethod<T>(Type type) where T : MyBaseType
{
}

public List<T> getall<T>()where T : employee
{
    type t = typeof(T)
    switch (t.name)
    {
        case "manager":
            List<manager> all = this.GetManagers()
            break;
        default
            List<sales> all = this.getSales()

    }

    return all 
}

public List<T> GetAll<T>() where T : Employee
 {
     List<T> all = new List<T>();
     if (typeof(T) == typeof(Manager))
         all = GetManagers() as List<T>;
     else
         all = GetSales() as List<T>;
     return all;
 }

var managers = getall<manager>();

var managers = getAllManagers();