What is difference Between protected void Page_Load(object sender, EventArgs e) and protected void btn_edit_Click(object sender, EventArgs e) where as i declare a table through this code adpt2 = new MySql.Data.MySqlClient.MySqlDataAdapter("select * from tbluser", cn); adpt2.Fill(ds, "user"); in pageload function and after that i can used this table user can access in anywhere but when i declared this table within the btn_edit_click event that time i can't used this table outside this function. Why?