c# - How can I get the content of 2 columns and show this? -

    public void showfirstfivehighscore()     {         string query = "select 'key', 'playername', 'highscore' playerpoints order highscore desc limit 5";          if (this.openconnection() == true)         {             mysqlcommand cmd = new mysqlcommand(query, _connection);              mysqldatareader reader = cmd.executereader();              while (reader.read())             {                messagebox.show(reader.getstring(...);             }              cmd.executenonquery();             this.closeconnection();         }     } 

i try show columns "playername" , "highscore". maybe in messagebox? help? thanks.

first of all, don't need use single quotes (') column names when call them in select part in query. need use character values.

second of all, mysqldatareader.getstring method takes int parameter zero-based column number. means can specify columns 1 , 2 , show them want.

key reserved word in mysql. need quote ` character. however, best solution change name nonreserved word.

your executenonquery meaningless select statement. doesn't anything @ all.

you need use using statement dispose mysqlcommand , mysqldatareader (also mysqlconnection when write).

string query = "select `key`, playername, highscore playerpoints order highscore desc limit 5"; using(mysqlcommand cmd = new mysqlcommand(query, _connection)) using(mysqldatareader reader = cmd.executereader()) {       while (reader.read())       {            messagebox.show(string.format("playername: {0} highscore: {1}",                                           reader.getstring(1),                                           reader.getstring(2)));       } } 

thank @soner. works. how can show 5 results in messagebox? not in 5 different messageboxes?

then can concatenate 5 rows in 1 string inside while statement , show outside of while statement. like;

string s = ""; while (reader.read()) {     s += string.format("playername: {0} highscore: {1}\n",                         reader.getstring(1),                         reader.getstring(2))); } messagebox.show(s);