Question

I am entering the source name userid and password through the textbox and want the database list should be listed on the combo box so that all the four options sourcename, userid, password and databasename can be selected by the user to perform the connectivity

The databases are to be retrieve from other system as per the user. User will enter the IP, userid and password and they should get the database list in the combo box so that they can select the required database and perform the connectivity

private void frmConfig_Load(object sender, EventArgs e)
{
    try
    {
        string Conn = "server=servername;User Id=userid;" + "pwd=******;";
        con = new SqlConnection(Conn);
        con.Open();

        da = new SqlDataAdapter("SELECT * FROM sys.database", con);
        cbSrc.Items.Add(da);
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}

I am trying to do this but it is not generating any data

Answer 1

sys.databases

SELECT name
FROM sys.databases;

Edit:

I recommend using IDataReader, returning a List and caching the results. You can simply bind your drop down to the results and retrieve the same list from cache when needed.

public List<string> GetDatabaseList()
{
    List<string> list = new List<string>();

    // Open connection to the database
    string conString = "server=xeon;uid=sa;pwd=manager; database=northwind";

    using (SqlConnection con = new SqlConnection(conString))
    {
        con.Open();

        // Set up a command with the given query and associate
        // this with the current connection.
        using (SqlCommand cmd = new SqlCommand("SELECT name from sys.databases", con))
        {
            using (IDataReader dr = cmd.ExecuteReader())
            {
                while (dr.Read())
                {
                    list.Add(dr[0].ToString());
                }
            }
        }
    }
    return list;

}