c# - How to solve this "error in your SQL syntax" -


i have connected database windows form, put values of database table column @ listbox, , want following: when select item listbox, column of table appear in textbox. more specific, drink names appear @ listbox( espresso,water etc) , want price appear @ textbox , when selected listbox. used following code that:

  private void listbox1_selectedindexchanged(object sender, eventargs e)     {         string constring =      "datasource=localhost;port=3306;username=root;password=root;";         string query = "select * apps.drinks drink_name ='" + listbox1.text + "'; ";         mysqlconnection condatabase = new mysqlconnection(constring);         mysqlcommand cmddatabase = new mysqlcommand(query, condatabase);         mysqldatareader myreader;         condatabase.open();         myreader = cmddatabase.executereader();         while (myreader.read())         {             string dprice = myreader.getstring("drink_price");             pricebox.text = dprice;         }      }

after debug project, shows items @ listbox, when select them error "you have error in sql syntax; check manual corresponds mysql server version right syntax use near '='espresso'' @ line 1"

the code database following: 

drop table if exists `apps`.`drinks`; create table  `apps`.`drinks` (   `drink_name` varchar(45) not null,   `drink_price` varchar(45) not null,   primary key (`drink_name`) ) engine=innodb default charset=utf8;  insert apps.drinks (drink_name,drink_price)     values ('nes','1'),('espresso','1'), (...)

please can me??

the query fails on is:

"select * apps.drinks drink_name ='" + listbox1.text + "'; "

there have is = incorrect, remove is query looks like:

"select * apps.drinks drink_name ='" + listbox1.text + "'; "

also take comment of w0lf , use prepared statements prevent sql injection.


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