I have removed the .asmx file and now try to run the Webmethod directly in the .ascx instead.
It works in a ASP.net WebApplication Webform(.Aspx Web Form)
[System.Web.Services.WebMethod]
public static string[] GetNames(string prefixText, int count)
{
List<String> hits = new List<String>();
SqlConnection conn = new SqlConnection();
conn.ConnectionString = "Data Source=(local);Initial Catalog=umbracodb;Integrated Security=True";
conn.Open();
SqlCommand cmd = conn.CreateCommand();
cmd.Parameters.Add("@Input", SqlDbType.VarChar, 50);
cmd.Parameters["@Input"].Value = "%" + prefixText + "%";
cmd.CommandText = "SELECT [Name] FROM [Product] WHERE [Name] like @Input";
cmd.ExecuteNonQuery();
SqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
hits.Add(reader["Name"].ToString());
}
conn.Close();
conn.Dispose();
return hits.ToArray();
}