class MySQLCon
{
 MYSQL mysql;
public:
 int errornum;
 string errortext;
public:
 //初始化
 MySQLCon();
 //關(guān)閉數(shù)據(jù)庫
 ~MySQLCon();
 //鏈接數(shù)據(jù)庫
 bool OpenConn(const char* host,const char* username,const char* pwd,const char* dbName,unsigned port=0);
 void GetErrorText();//獲取錯(cuò)誤文本
 void Close();//關(guān)閉數(shù)據(jù)庫
 bool ExecuteSQL(const char* sql);//使用SQL語句,無法接收數(shù)據(jù)
 bool QureySQL(const char* sql, vectorvectorstring>> resultSet);//使用SQL語句并接收數(shù)據(jù)(select語句)
};

MySQLCon::MySQLCon()
{
 if (mysql_library_init(0, nullptr, nullptr)) 
 {
 cout  "CAPI初始化失敗"  std::endl;
 getchar();
 exit(1);
 }
 if (mysql_init(mysql)==nullptr)
 {
 cout  "初始化數(shù)據(jù)庫變量失敗"  std::endl;
 getchar();
 exit(1);
 }
 if (mysql_options(mysql, MYSQL_SET_CHARSET_NAME, "gbk"))
 {
 cout  "設(shè)置連接選項(xiàng)失敗"  std::endl;
 getchar();
 exit(1);
 }
}

//參數(shù)分別為主機(jī),用戶名,密碼,數(shù)據(jù)庫名,端口號(hào)
bool MySQLCon::OpenConn(const char* host, const char* username, const char* pwd, const char* dbName, unsigned port)
{
 //連接數(shù)據(jù)庫
 if (mysql_real_connect(mysql, host, username, pwd, dbName, port, nullptr, 0)==nullptr)
 {
 cout  "連接到MySQL服務(wù)器失敗"  std::endl;
 //獲取錯(cuò)誤文本
 GetErrorText();
 exit(1);
 return false;
 }
 return true;
 
}

void MySQLCon::GetErrorText()
{
 //獲取錯(cuò)誤代碼
 errornum = mysql_errno(mysql);
 //獲取錯(cuò)誤文本
 errortext = mysql_error(mysql);
 //打印錯(cuò)誤代碼
 cout  "error num: "  errornum  std::endl;
 //打印錯(cuò)誤文本
 cout  "error text: "  errortext  std::endl;
 getchar();
}

bool MySQLCon::ExecuteSQL(const char* sql)
{
 //使用SQL語句但無法接收數(shù)據(jù)
 if (mysql_real_query(mysql, sql, strlen(sql)))
 {
 GetErrorText();
 return false;
 }
 return true;
}

bool MySQLCon::QureySQL(const char* sql, vectorvectorstring>> resultSet)
{
 //使用SQL語句并接收數(shù)據(jù)至vector容器
 if (mysql_real_query(mysql, sql, strlen(sql)))
 {
 GetErrorText();
 return false;
 }
 //創(chuàng)建一個(gè)MYSQL結(jié)果集
 MYSQL_RES* result = mysql_store_result(mysql);
 //獲取行和列的總數(shù)
 unsigned int rows = mysql_num_rows(result);
 unsigned int cols = mysql_num_fields(result);
 //用于記錄結(jié)果集中的一條數(shù)據(jù)
 MYSQL_ROW row;
 while (row = mysql_fetch_row(result))
 {
 //創(chuàng)建一個(gè)vector容器用于儲(chǔ)存row中的數(shù)據(jù)
 vectorstring> lineDate;
 for (int i = 0; i  cols; i++)
 {
 if (row[i])
 {
 //將row中每一列的數(shù)據(jù)存入lineDate中
 lineDate.push_back(row[i]);
 }
 else
 {
 lineDate.push_back("");
 }
 }
 //在resultSet中存入整行數(shù)據(jù)
 resultSet.push_back(lineDate);
 }
 //釋放結(jié)果集
 mysql_free_result(result);
 return true;
}

void MySQLCon::Close()
{
 mysql_close(mysql);
}
MySQLCon::~MySQLCon()
{
 Close();
 mysql_library_end();
}

int main()
{
 MySQLCon c_apiconn;
 c_apiconn.OpenConn("127.0.0.1", "root", "136119", "fancy");
 string sql = "use fancy;";
 vectorvectorstring>> data;
 c_apiconn.ExecuteSQL(sql.c_str());
 sql = "select * from fancy.info;";
 c_apiconn.QureySQL(sql.c_str(), data);
 for (int i = 0; i  data.size(); i++)
 {
 for (int j = 0; j  data[i].size(); j++)
 {
 cout  data[i][j]  "\t";
 }
 cout  endl;
 }
 return 0;
}