MFC封装的MySQL操作类

// SQLConnection.cpp: implementation of the CSQLConnection class. // ////////////////////////////////////////////////////////////////////// #include "stdafx.h" #include "SQLConnection.h" #include "SQLResult.h" #ifdef _DEBUG #undef THIS_FILE static char THIS_FILE[]=__FILE__; #define new DEBUG_NEW #endif IMPLEMENT_DYNAMIC(CSQLConnection, CSQLBase) /****************************************************************************** Function: CSQLConnection::CSQLConnection Purpose: Constructor Remarks: Call the Open function to establish the connection before every other database operations. ******************************************************************************/ CSQLConnection::CSQLConnection() : CSQLBase(NULL) { } /****************************************************************************** Function: CSQLConnection::~CSQLConnection Purpose: Destructor. Closes the database connection. ******************************************************************************/ CSQLConnection::~CSQLConnection() { Close(); // close the database connection and frees the connection handle } /****************************************************************************** Function: CSQLConnection::Open Purpose: Connect to database Parameters: pszHost - Host name pszDatabase - Database name pszUser - user name nPort - port number; default 3306 Exceptions: - mysql_init fails - mysql_real_connect fails ******************************************************************************/ void CSQLConnection::Open(LPCTSTR pszHost, LPCTSTR pszDatabase, LPCTSTR pszUser, LPCTSTR pszPassword, UINT nPort /*=3306*/) { Close(); m_hConnect = mysql_init(NULL); ThrowExceptionIfNotOpen(); HCONNECT hConnect = mysql_real_connect(m_hConnect, pszHost, pszUser, pszPassword, pszDatabase, nPort, NULL, 0 ); // if mysql_real_connect failed then returns NULL // but first argument, m_hConnect, which was initialized by // mysql_init can be further used to get the error if(NULL == hConnect) { ThrowException(); // m_hConnect is used to get the error } } /****************************************************************************** Function: CSQLConnection::Close Purpose: Closes the database connection and free the connection handle ******************************************************************************/ void CSQLConnection::Close() { if(NULL != m_hConnect) { // close the database connection // mysql_close also frees the connection handle mysql_close(m_hConnect); m_hConnect = NULL; } } /****************************************************************************** Function: CSQLConnection::IsOpen Purpose: checks if database connetion is open ******************************************************************************/ bool CSQLConnection::IsOpen() { return (NULL != m_hConnect); } /****************************************************************************** Function: CSQLConnection::TransBegin Purpose: Begin transcation ******************************************************************************/ void CSQLConnection::TransBegin() { ExecuteSQL("START TRANSACTION"); } /****************************************************************************** Function: CSQLConnection::TransCancel Purpose: Rollback transcation ******************************************************************************/ void CSQLConnection::TransCancel() { ExecuteSQL("ROLLBACK"); } /****************************************************************************** Function: CSQLConnection::TransCommit Purpose: Commit transcation ******************************************************************************/ void CSQLConnection::TransCommit() { ExecuteSQL("COMMIT"); } /****************************************************************************** Function: CSQLConnection::ExecuteSQL Parameters: pszSQL - the query statement Purpose: Executes SQL statements that do not require result-set Exceptions: connection is not opened mysql_query fails ******************************************************************************/ void CSQLConnection::ExecuteSQL(LPCTSTR pszSQL) { ThrowExceptionIfNotOpen(); if(0 != mysql_query(m_hConnect, pszSQL)) { ThrowException(); } } /****************************************************************************** Function: CSQLConnection::ExecuteSQLV Parameters: pszFormat - the format control string ... - variable list of arguments Purpose: Executes SQL statements those do not require result-set The SQL statement is built according to the format control string and the variable list of arguments. Exceptions: Thrown by ExecuteSQL ******************************************************************************/ void CSQLConnection::ExecuteSQLV(LPCTSTR pszFormat, ...) { CString strSQL; // formats the string them pass it to ExecuteSQL function va_list args; va_start(args, pszFormat); strSQL.FormatV(pszFormat, args); ExecuteSQL(strSQL); } /****************************************************************************** Function: CSQLConnection::GetOneRow Parameters: pszSelect - SELECT statement arrValues - array of CSQLValues to retrieve Purpose: Get a single row from a recordset Exceptions: Thrown by CSQLResult::Query and CSQLResult::Fetch ******************************************************************************/ bool CSQLConnection::GetOneRow(LPCTSTR pszSelect, SQLValueArray& arrValues) { CSQLResult res(*this); res.Query(pszSelect); return res.Fetch(arrValues); } /****************************************************************************** Function: CSQLConnection::GetOneRowV Parameters: arrValues - array of CSQLValues to retrieve pszFormat - the format control string ... - variable list of arguments Purpose: Get a single row from a recordset The SQL statement is built according to the format control string and the variable list of arguments. Exceptions: Thrown by CSQLResult::Query and CSQLResult::Fetch ******************************************************************************/ bool CSQLConnection::GetOneRowV(SQLValueArray& arrValues, LPCTSTR pszFormat, ... ) { CString strSelect; // formats the string them pass it to GetOneRow function va_list args; va_start(args, pszFormat); strSelect.FormatV(pszFormat, args); return GetOneRow(strSelect, arrValues); } /****************************************************************************** Function: CSQLConnection::UpdateBLOBField Parameters: value - contains value to update pszTable - table name pszField - BLOB field name pszWhere - WHERE condition; default NULL Purpose: Update a BLOB field Exceptions: connection is not opened mysql_real_query fails ******************************************************************************/ void CSQLConnection::UpdateBLOBField(const CSQLValue& value, LPCTSTR pszTable, LPCTSTR pszField, LPCTSTR pszWhere /*=NULL*/) { _ASSERTE(true == value.IsBLOB()); // please, call this function only for BLOB type ThrowExceptionIfNotOpen(); CString strQueryBegin, strQueryEnd; strQueryBegin.Format(_T("UPDATE %s SET %s='"), pszTable, pszField); if(NULL == pszWhere) { strQueryEnd = _T("'"); } else { strQueryEnd.Format(_T("' WHERE %