C# database path -

tomorrow i'll go c# competition. we'll have use databases , our sources tested on different computer can't hardcode connectionstring this:

sqlconnection connection = new sqlconnection(@"c:\users\radu\documents\visual studio 2013\projects\windowsformsapplication12\windowsformsapplication12\database1.mdf"); 

i compiled code:

private void button1_click(object sender, eventargs e)     {         string mdfpath = path.combine(application.startuppath, "database1.mdf");         sqlconnection connection = new sqlconnection(@"data source=(localdb)\v11.0;attachdbfilename=" + mdfpath + ";");          connection.open();          string commandstring = "select * conturi";         sqlcommand command = new sqlcommand(commandstring, connection);         sqldatareader reader = command.executereader();           while(reader.read())         {             messagebox.show(reader.getstring(1) + reader.getstring(2));         }         reader.close();           string commandstring1 = "insert conturi (nume, parola) values (@name, @pass)";         sqlcommand command1 = new sqlcommand(commandstring1, connection);         command1.parameters.addwithvalue("name", textbox1.text.tostring());         command1.parameters.addwithvalue("pass", textbox2.text.tostring());         command1.executenonquery();       } 

it let me read data in database first statement can't insert data db. if hardcode path insertion work.