c# - retrieving a datalist created in one void and displaying it in another -

i have question calling data 1 method another.

basically have tasked myself condensing , simplifying code. in scenario connecting .mdb file , reading 1 bit of data it. had connection string in spots needed, after learning more , more classes , stuff informed copying , pasting bad. wanted take connection string , make it...it's own void call variables needed spots. problem how return datalist retrieved db? here code have works fine.

string directory = @"c:\";             string[] folders = directory.getdirectories(directory, "rameses-*");             list<string> datalist = new list<string>();             foreach (string foldername in folders)             {                 using (var conection = new system.data.oledb.oledbconnection("provider=microsoft.jet.oledb.4.0;" + "data source=" + foldername + "\\program\\random.mdb;jet oledb:database password=******"))                 {                     conection.open();                     var query = "select u_company t_user";                     var command = new system.data.oledb.oledbcommand(query, conection);                     var reader = command.executereader();                     while (reader.read())                     {                         datalist.add(reader[0].tostring());                     }                     reader.close();                     conection.close();                 }             }             error_handling(" alternate profiles loaded selector");             profselect.datasource = datalist;             profselect.selectedtext = datalist.last(); 

but thought able take connection out of it's current spot , can't datalist inital connection drop down. suggestions?

        //database connection base function     public static void database_link(string query, string foldername)     {         list<string> datalist = new list<string>();         using (var conection = new system.data.oledb.oledbconnection("provider=microsoft.jet.oledb.4.0;" + "data source=" + foldername + "\\program\\random.mdb;jet oledb:database password=****"))         {             conection.open();             var command = new system.data.oledb.oledbcommand(query, conection);             var reader = command.executereader();             while (reader.read())             {                 datalist.add(reader[0].tostring());             }             reader.close();             conection.close();         }     }      // ramdata check , load files , database     private void ramdata_check(object sender, eventargs e)     {         try         {             string directory = @"c:\";             string[] folders = directory.getdirectories(directory, "myapp-*");             list<string> datalist = new list<string>();             foreach (string foldername in folders)             {                 database_link("select u_company t_user", foldername);             }             error_handling(" alternate profiles loaded selector");             profselect.datasource = datalist;             profselect.selectedtext = datalist.last();         }         catch {} 

don't make shared connection call void: make create connection, open , return it. using block close connection when completes don't need manually close it:

public oledbconnection openconnection() {       var result = new oledbconnection("my special connection string here"))      result.open()      return result;  }  public list<string> void dosomethingwithconnection()  {     using (var connection = openconnection());     {         list<string> datalist = new list<string>();          oledbcommand command = new oledbcommand("dosomethinghere", connection);         var reader = command.executereader();         while (reader.read())         {             datalist.add(reader[0].tostring());         }          return datalist;     // connection automatically closed when      // code exits using block.     } }