multiple mssql connection string in class c#

Goran Bibic

7y913Learn iOS Programming

Need for my app

Have database 2017,2018,2019...I add IN every form connection string

string BSS_2017 = Properties.Settings.Default.MG_SISTEM_2017CS; string BSS_2018 = Properties.Settings.Default.MG_SISTEM_2018CS;
string BSS_2019 = Properties.Settings.Default.MG_SISTEM_2019CS;
string con;

Then in label chek value (2017,2018 or2019)

public popis()
{
InitializeComponent();
yearlabel.Text = getYear();
}

And connect

private String getGodina()
{
string value = login.godina.ToString();
return value;
}
public void PullData()
{
if (yearlabel.Text == "2017")
{
con = BSS_2019;
}
else if (yearlabel.Text == "2018")
{
con = BSS_2018;
}
else if (yearlabel.Text == "2019")
{
con = BSS_2019;
}
}

That work fine...but...I must put this in every form in my app....need help

To create some class with this value.

Help?

7 Replies

Know the answer? Post it — somebody with the same question will find it here.

Amit Mohanty7y ago
Accepted answer
Hey create a separate class for connection and use it.
public class ConnectionClass
{
    static string BSS_2017 = Properties.Settings.Default.MG_SISTEM_2017CS;
    static string BSS_2018 = Properties.Settings.Default.MG_SISTEM_2018CS;
    static string BSS_2019 = Properties.Settings.Default.MG_SISTEM_2019CS;
    static string con;

    public static string PullData(string numYear)
    {
        switch (numYear)
        {
            case "2017":
                con = BSS_2017;
                break;
            case "2018":
                con = BSS_2018;
                break;
            case "2019":
                con = BSS_2019;
                break;
        }
        return con;
    }
}
Then call the function where you want.
string conString = ConnectionClass.PullData(yearlabel.Text);
Amit Mohanty7y ago
Hey Goran first check what you get in conString variable.
Goran Bibic7y ago
Amit Mohanty

Intialize component
string conString = ConnectionClass.PullData(yearlabel.Text);

I put this when fill datagrid and have error

Line 16 // Connection string proprerty has not intialized.
  private void Ulazni_racun_roba_lista_fill()
        {

//your string
            string conString = ConnectionClass.PullData(godinalabel.Text);

            using (SqlConnection openCon = new SqlConnection(conString))

            {

String saveStaff = "SELECT * from dbo.popis_lista";


                Console.WriteLine(saveStaff);

//Here erorr  connection string proprerty has not intialized.
                    openCon.Open();

                    using (SqlDataAdapter querySaveStaff = new SqlDataAdapter(saveStaff, conString))

                    {

                        DataTable dt = new DataTable();


                        querySaveStaff.Fill(dt);
                        PopisListaDataGridView.DataSource = dt;
                    PopisListaDataGridView.SelectionMode = DataGridViewSelectionMode.FullRowSelect;

PopisListaDataGridView.Update();
                    PopisListaDataGridView.Refresh();

}

                }



            }
Goran Bibic7y ago
Rajanikant Hawaldar

Yes. Need example what need to be in class?
Rajanikant Hawaldar7y ago
Create class implement singleton design pattern in class then move common code then you can accessing at all forms through class singleton instance.
Goran Bibic7y ago
Yes. But need solution...recomandition...proposal
Jaish Mathews7y ago
why can't each form derive from a base from and any connection related code move there?

multiple mssql connection string in class c#

Amit Mohanty

Rajanikant Hawaldar