C ++ and C # simple sample code for accessing MySQL

Paste the sample code. It is very suitable for beginners. 1) C # access mysqlusing System; using System. collections. generic; using System. text; using MySql. data. mySqlClient; using System. data; using System. data. common; namespace SybaseUtilTest {class Program {// http://bugs.mysql.com/47422, interested friends, you can see how this bug is going static void testDataAdapter () {try {MySqlClientFactory factory = MySqlClientFactory. instance; DbConnection conn = factory. createConnection (); conn. C OnnectionString = string. format ("server = {0}; user id = {1}; password = {2}; database = {3}; port = {4}; pooling = false ", "localhost", "root", "passwd", "test", 3306); conn. open (); DbDataAdapter da = factory. createDataAdapter (); da. selectCommand = conn. createCommand (); da. selectCommand. commandText = "select * from t12345"; da. deleteCommand = conn. createCommand (); da. deleteCommand. commandText = "delete from t 12345 where id = @ id "; DbParameter param = factory. createParameter (); param. parameterName = "@ id"; param. dbType = DbType. int32; param. sourceColumn = "id"; param. sourceVersion = DataRowVersion. current; da. deleteCommand. parameters. add (param); da. deleteCommand. updatedRowSource = UpdateRowSource. none; DataTable dt = new DataTable ("t12345"); da. fill (dt); int index = 0; foreach (DataRow o in dt. rows) {If (o ["id"]. equals (4) {Console. writeLine (String. format ("index = {0}, to delete id = 4, col2 = {1}", index, o ["col2"]); break ;} index ++;} dt. rows [index]. delete (); da. update (dt); dt. acceptChanges (); da. dispose (); conn. close ();} catch (Exception ex) {Console. writeLine (ex. source + "" + ex. message + "" + ex. stackTrace) ;}} static void Main (string [] args) {testDataAdapter () ;}} 2) C ++ access (Directly call C-API) # include <iostream> # include <windows. h> # include <mysql. h ># include <string> static const char host [32] = "localhost"; static const char user [32] = "test "; static const char passwd [32] = "passwd"; static const char db [32] = "test";/** mysql> select * from t; + ---- + | id | + ---- + | 1 | + ---- + 1 row in set (0.00 sec) mysql> delimiter // mysql> create procedure get_t (in t1 int) -> begin-> Select id from t where id = t1;-> end-> // Query OK, 0 rows affected (0.05 sec) mysql> call get_t (1 ); -> // + ---- + | id | + ---- + | 1 | + ---- + 1 row in set (0.00 sec) Query OK, 0 rows affected (0.00 sec) */void test_more_results (MYSQL * h) {char str [512] = "insert into test_num values (101); insert into test_num values (122); commit ;"; int r = mysql_real_query (h, str, strlen (str); if (r) {const ch Ar * error = mysql_error (h); std: cout <"*** Connection Error" <error <std: endl ;} do {MYSQL_RES * res = mysql_store_result (h); mysql_free_result (res);} while (0 = mysql_next_result (h);} void test_proc_stmt (MYSQL * h) {MYSQL * mysql _ = h; MYSQL_BIND bind; MYSQL_BIND obind [1]; // test_more_results (mysql _); MYSQL_STMT * hStmt = ignore (mysql _); my_bool true_value = 1; mysql_stmt_a Ttr_set (hStmt, STMT_ATTR_UPDATE_MAX_LENGTH, (void *) & true_value); char SQL [] = "call get_t (?) "; // Char SQL [] =" select id from t where id =? "; If (mysql_stmt_prepare (hStmt, SQL, strlen (SQL) {std: cout <__line __< <": stmt prepare error: "<(mysql_stmt_error (hStmt) <std: endl; mysql_stmt_reset (hStmt); if (mysql_stmt_prepare (hStmt, SQL, strlen (SQL) {std :: cout <__line __< <": stmt prepare error:" <(mysql_stmt_error (hStmt) <std: endl; mysql_close (mysql _); exit (-1) ;}} int id = 1; unsigned long id_len = 0; memset (& bind, 0, sizeof (B Ind); bind. buffer_type = FIELD_TYPE_LONG; bind. buffer = (void *) & id; bind. is_unsigned = true; bind. length = & id_len; // bind [0]. buffer_length = sizeof (id); // bind [0]. is_null = 0; if (mysql_stmt_bind_param (hStmt, (MYSQL_BIND *) (& bind ))! = 0) {std: cout <__line __< <": stmt prepare error:" <(mysql_stmt_error (hStmt) <std: endl; mysql_close (mysql _); exit (-1);} if (mysql_stmt_execute (hStmt )! = 0) {std: cout <__line __< <": stmt prepare error:" <(mysql_stmt_error (hStmt) <std: endl; mysql_close (mysql _); exit (-1);} int t2; memset (obind, 0, sizeof (obind); obind [0]. buffer_type = MYSQL_TYPE_LONG; obind [0]. buffer = (char *) & t2; obind [0]. buffer_length = sizeof (t2); if (mysql_stmt_bind_result (hStmt, (MYSQL_BIND *) & obind [0])! = 0) {std: cout <__line __< <": stmt prepare error:" <(mysql_stmt_error (hStmt) <std: endl; mysql_close (mysql _); exit (-1);} if (mysql_stmt_store_result (hStmt )! = 0) {std: cout <__line __< <": stmt prepare error:" <(mysql_stmt_error (hStmt) <std: endl; mysql_close (mysql _); exit (-1);} int rows = mysql_stmt_num_rows (hStmt); for (int I = 0; I <rows; I ++) {if (mysql_stmt_fetch (hStmt) = 0) {std: cout <"id =" <t2 <std: endl ;}} mysql_stmt_free_result (hStmt ); mysql_stmt_close (hStmt);} // Just for demo only. // int main () {MYSQL * mysql _ = NULL; MYSQL_RES * result _ = NULL; MYSQL_ROW row _; mysql _ = mysql_init (mysql _); // if (mysql_real_connect (mysql _, host, user, passwd, db, 3306, NULL, CLIENT_MULTI_STATEMENTS) = NULL) if (mysql_real_connect (mysql _, host, user, passwd, db, 3306, NULL, CLIENT_MULTI_STATEMENTS) = NULL) {const char * error = mysql_error (mysql _); std :: cout <"*** Connection Error" <error <std: endl; return-1;} mysql_autocommit (mysql _, false); std :: string encodeStr = "set names 'gbk'"; mysql_real_query (mysql _, encodeStr. c_str (), encodeStr. size ();/* const char * tmpTableName = "t"; // assume you are querying the table 't'char str [512]; int cnt = 0; sprintf (str, "select count (*) as cnt from % s", tmpTableName); mysql_real_query (mysql _, str, strlen (str )); result _ = mysql_store_result (mysql _); while (row _ = mysql_fetch_row (result _) {// get the field value if (row _ [0]) {std :: cout <"count =" <row _ [0] <std: endl; // convert it into int cnt = atoi (row _ [0]); std:: cout <"cnt value =" <row _ [0] <std: endl ;}} mysql_free_result (result _); test_more_results (); */test_proc_stmt (mysql _); do {MYSQL_RES * res = mysql_store_result (mysql _); mysql_free_result (res);} while (0 = mysql_next_result (mysql _))); test_proc_stmt (mysql _); mysql_close (mysql _); return 0 ;}