C＃更新/刷新GridView

Question

When I'm trying to update my gridview. The changes won't show up. But when I reopen the form it has changed. How can I make sure that it will update immediately (and show up). When I say:

            scb = new SqlCommandBuilder(da);
            da.Fill(dt);
            userInformation.DataSource = dt;

It wil obviously fill the table. But than I have the information twice.

This is my code currently:

            DataTable dt;
            SqlDataAdapter da;
            SqlCommand cmd;
            SqlCommandBuilder scb;

            //this is inside the constructor
            cmd = new SqlCommand("loadUserTable", conn);
            cmd.Parameters.AddWithValue("@username", this.username);
            cmd.CommandType = CommandType.StoredProcedure;
            da = new SqlDataAdapter(cmd);
            da.SelectCommand = cmd;
            dt = new DataTable();
            da.Fill(dt);
            userInformation.DataSource = dt;

            //this is a button (called save)
            scb = new SqlCommandBuilder(da);
            da.Update(dt);
            userInformation.DataSource = dt;

Also I've tried refresh but that also doesn't do the job.

Answer 1

Each time you Fill an instance of DataTable , before you do so, you need to call the Clear() method on that DataTable . If not, the Fill method just keeps adding on to that DataTable .