OLE_DB 是基于COM接口,其访问速度,效率是最高的,ADO是基于OLE_DB的,在
效率方面是在OLE_DB之下,ODBC更不用提了,(别拍砖啊!)。但是OLE_DB相关的
资料甚少,我最进认真学习了一下OLE_DB,现已封装成一个类,现公开出来,有不足
之处,高手们多多指教。
这是类的头文件:------------------
#if !defined(AFX_ADODATABASE_H__CC00630B_09FF_483D_81AB_7DC19E3EA26A__INCLUDED_) #define AFX_ADODATABASE_H__CC00630B_09FF_483D_81AB_7DC19E3EA26A__INCLUDED_
#if _MSC_VER > 1000 #pragma once #endif
#define MAX_FIELDS 255 /*一个表中最大字段数 */ #define MAX_FIELDS_LEN 30 /*字段名字最大字节数 */ #define MAX_FIELDS_DATA_LEN 280 /*字符字段中字符的最大字节数 */
class COLEDBDatabase { public: void MyGetColumnValue(); void ConvertNumericToChar(); void RollbackTran(); void CommitTran(); void StartTran(); BOOL NextMatchingRecord(); int SelectMatchingRecords(char *szWhere); BOOL ExecuteQuery(char *szQuery); BOOL UpdateRecord(char *szWhere); void Quote(char* sText); BOOL AddRecord(); BOOL ExecuteSQL(char *szSQL); BOOL ConnectDB2(char *szServerName, char *szDatabase, char *szUid, char *szPwd); BOOL ConnectDB1(char* szDNS,char* szUid,char* szPwd); BOOL ConnectDB(CDBPropSet dbPropSet); void DisconnectionDB(); CAdoDatabase(); virtual ~CAdoDatabase();
/*-----------置换用到----------------------------- */ string szOld ,szNew ; int nPos ,nGet ; BOOL bReplace ;
/*-------------OLE DB 操作---------------------------*/ char m_Provider[20] ; /*数据库提供着 MSDASQL SQLOLEDB */ CDataSource m_DataSource ; /*数据源句柄 */ CSession m_Session ; /*会话句柄 */ CCommand <CNoAccessor,CNoRowset> m_CmdExecute ; /*公共执行SQL句柄【注,没有行集返回】 */ HINSTANCE hInstance ; /*取得错误的句柄 */ CCommand<CDynamicAccessor,CRowset> m_CmdQuery;
/*------------------ 列信息----------------*/ DBSTATUS dbStatus ; /*用于判断该列是否为空*/ DBCOLUMNINFO *m_pColsInfo; /*列信息*/ ULONG m_nColCount; /*列总数*/ LPOLESTR m_pStrBuffer; /**/ unsigned long nColType ; /*列类型*/ LONG dbLong ; /*用于取 整形列*/ DB_NUMERIC dbNumeric ; /*用于取 Numeric列*/ char szNumeric[20] ; /*用于辅助取 Numeric*/ unsigned int nNumericLen ; /*用于取 Numeric 列*/ __int64 dbInt64 ; /*用于取 Numeric列 只用*/
/*--------------------时间、日期处理---------------------*/ DBTIME dbTime ; /*时间 20:12:20 */ DBDATE dbDate ; /*日期 2003-10-31 */ DBTIMESTAMP dbTimeStamp; /*时间戳 2003-10-31 20:12:20 */
BOOL m_bOpen ; /*是否打开 */ char m_szExecute[1024*3]; /*执行语句 */ char m_szErrMsg[1024] ; /*错误信息*/ HRESULT hr; int ff ; string szText1 ;
/*-------------临时绑定表--------------------*/ char m_szTableName[255] ; /*临时绑定表名称*/ int m_nFields; /*临时绑定表字段的总数*/ char m_sFieldName[MAX_FIELDS] [MAX_FIELDS_LEN]; /*临时绑定表字段名字*/ char m_sFieldValue[MAX_FIELDS][MAX_FIELDS_DATA_LEN]; /*临时绑定表字段值*/ int m_bNumeric[MAX_FIELDS] ; /*临时绑定表字段是否为数值类型 1 int 2 varchar 3 numeric 4 date */
protected: void GetExecError(); };
#endif
以下是类的实现文件 --------------------------
/*罗家兄弟 2004-05-12*/
#include "stdafx.h" #include "OLEDBDatabase.h"
COLEDBDatabase::COLEDBDatabase() { m_bOpen=FALSE ; szOld="'" ; szNew ="''" ; hInstance = NULL ; }
COLEDBDatabase::~COLEDBDatabase() {
}
/*断开连接 */ void COLEDBDatabase::DisconnectionDB() { if(m_bOpen) { m_CmdExecute.ReleaseCommand() ; file://必须调用 */ m_CmdQuery.ReleaseCommand() ; file://必须调用 */ m_Session.Close() ; m_DataSource.Close() ; m_bOpen=FALSE ; } if(hInstance !=NULL) {/*释放句柄 */ ::FreeLibrary(hInstance) ; hInstance = NULL ; } }
/*连接数据库 */ BOOL COLEDBDatabase::ConnectDB(CDBPropSet dbPropSet) { if(m_bOpen) DisconnectionDB(); hInstance = ::LoadLibrary("MSDAERR.DLL") ; hr=m_DataSource.Open(m_Provider,&dbPropSet) ; if(FAILED(hr)) goto end ; hr=m_Session.Open(m_DataSource) ; if(FAILED(hr)) goto end ; m_bOpen = TRUE ; return TRUE ; end: { m_bOpen=FALSE ; GetExecError() ; return FALSE ; } }
/*连接数据库1 szDNS -> ODBC 的DNS szUid -> 用户名 szPwd -> 密码 */ BOOL COLEDBDatabase::ConnectDB1(char *szDNS, char *szUid, char *szPwd) { CDBPropSet dbinit(DBPROPSET_DBINIT);
dbinit.AddProperty(DBPROP_INIT_DATASOURCE, szDNS); dbinit.AddProperty(DBPROP_AUTH_USERID, szUid); dbinit.AddProperty(DBPROP_AUTH_PASSWORD, szPwd); dbinit.AddProperty(DBPROP_INIT_PROMPT, (short)4); dbinit.AddProperty(DBPROP_INIT_LCID, (long)1033); strcpy(m_Provider,"MSDASQL") ; return ConnectDB(dbinit) ; }
/*连接数据库 说明:szServerName -> 是机器名字 或者IP地址 szUid -> 用户名 szPwd -> 密码 */ BOOL COLEDBDatabase::ConnectDB2(char *szServerName, char *szDatabase, char *szUid, char *szPwd) { CDBPropSet dbinit(DBPROPSET_DBINIT);
strcpy(m_Provider,"SQLOLEDB") ; dbinit.AddProperty(DBPROP_INIT_DATASOURCE, szServerName); dbinit.AddProperty(DBPROP_INIT_CATALOG, szDatabase); dbinit.AddProperty(DBPROP_AUTH_USERID, szUid); dbinit.AddProperty(DBPROP_AUTH_PASSWORD, szPwd); dbinit.AddProperty(DBPROP_INIT_PROMPT, (short)4); dbinit.AddProperty(DBPROP_INIT_LCID, (long)1033);
return ConnectDB(dbinit) ; }
/*执行一句SQL语句*/ BOOL COLEDBDatabase::ExecuteSQL(char *szSQL) { if(!m_bOpen) return FALSE ;
hr=m_CmdExecute.Open(m_Session,szSQL) ; if(FAILED(hr)) { GetExecError() ; m_CmdExecute.Close() ; m_CmdExecute.ReleaseCommand() ; return FALSE ; } m_CmdExecute.Close() ; m_CmdExecute.ReleaseCommand() ;
return TRUE ; }
/*增加一条记录 */ BOOL COLEDBDatabase::AddRecord() { if(!m_bOpen) return FALSE ;
if(m_nFields<=0) return FALSE ;
ff = 0 ; sprintf(m_szExecute,"Insert into %s(",m_szTableName) ; for(int i=0;i<m_nFields;i++) { if(ff>0) strcat(m_szExecute,",") ; strcat(m_szExecute,m_sFieldName[i]) ; ff ++ ; } strcat(m_szExecute,") values(") ; ff=0 ; for(i=0;i<m_nFields;i++) { if(ff>0) strcat(m_szExecute,",") ; if(m_bNumeric[i]==1 || m_bNumeric[i]==3) strcat(m_szExecute,m_sFieldValue[i]) ; else { strcat(m_szExecute,"'") ; Quote(m_sFieldValue[i]) ; strcat(m_szExecute,m_sFieldValue[i]) ; strcat(m_szExecute,"'") ; }
ff ++ ; }
strcat(m_szExecute,")") ; return ExecuteSQL(m_szExecute) ; }
/*置换 ' 为 '' 以防出错 建议在外部处理*/ void COLEDBDatabase::Quote(char* sText) { szText1=sText; bReplace = FALSE ; nPos = 0 ; nGet = 0 ; while(nGet!=-1) { nGet = szText1.find(szOld,nPos) ; if(nGet>0) { szText1.replace(nGet,szOld.length(),szNew) ; nPos = nGet + 2 ; bReplace = TRUE ; } } if(bReplace) strcpy(sText,szText1.c_str()) ; }
/*修改一记录 把数据设置好,带入修改条件,执行即可 */ BOOL COLEDBDatabase::UpdateRecord(char *szWhere) { if(!m_bOpen) return FALSE ;
if(m_nFields<=0) return FALSE ;
sprintf(m_szExecute,"Update %s Set ",m_szTableName) ; ff=0 ; for(int i=0;i<m_nFields;i++) { if(ff>0) strcat(m_szExecute,",") ; strcat(m_szExecute,m_sFieldName[i]) ; strcat(m_szExecute,"=") ; if(m_bNumeric[i]==1 || m_bNumeric[i]==3) strcat(m_szExecute,m_sFieldValue[i]) ; else { strcat(m_szExecute,"'") ; Quote(m_sFieldValue[i]) ; /*进行保护*/ strcat(m_szExecute,m_sFieldValue[i]) ; strcat(m_szExecute,"'") ; }
ff ++ ; } strcat(m_szExecute," where ") ; strcat(m_szExecute,szWhere) ; return ExecuteSQL(m_szExecute) ; }
/*执行查询*/ BOOL COLEDBDatabase::ExecuteQuery(char *szQuery) { if(!m_bOpen) return FALSE ; hr=m_CmdQuery.Open(m_Session,szQuery) ; if(FAILED(hr)) {/*出错处理*/ GetExecError() ; m_CmdQuery.Close() ; return FALSE ; } return TRUE ; }
/* 查找记录 参数:Where 后面的条件即可 返回值 : 1 ->有符合条件的值 0 ->没有符合条件的值 -1 ->出错 */ int COLEDBDatabase::SelectMatchingRecords(char *szWhere) { if(!m_bOpen) return FALSE ;
if(m_nFields<=0) return FALSE ;
sprintf(m_szExecute,"Select ") ; ff=0 ; for(int i=0;i<m_nFields;i++) { if(ff>0) strcat(m_szExecute,",") ; strcat(m_szExecute,m_sFieldName[i]) ; ff ++ ; } strcat(m_szExecute," From ") ; strcat(m_szExecute,m_szTableName) ; strcat(m_szExecute," Where ") ; strcat(m_szExecute,szWhere) ; if(!ExecuteQuery(m_szExecute)) return -1 ;
hr = m_CmdQuery.MoveFirst() ; if(hr!=S_OK) {/*没有记录*/ m_CmdQuery.Close() ; return 0 ; }else {/*有记录*/ MyGetColumnValue() ; } return 1 ; }
/*下一条记录*/ BOOL COLEDBDatabase::NextMatchingRecord() { hr=m_CmdQuery.MoveNext() ; if(hr!=S_OK) {/*移动失败*/ m_CmdQuery.Close() ; return FALSE ; }else {/*移动成功*/ MyGetColumnValue() ; } return TRUE ; }
void COLEDBDatabase::StartTran() { if(!m_bOpen) return ; m_Session.StartTransaction() ; }
void COLEDBDatabase::CommitTran() { if(!m_bOpen) return ; m_Session.Commit() ; }
void COLEDBDatabase::RollbackTran() { if(!m_bOpen) return ; m_Session.Abort() ; }
/*取得执行错误*/ void COLEDBDatabase::GetExecError() { LPVOID lpMsgBuf;
if(hInstance) { long l = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_HMODULE | FORMAT_MESSAGE_FROM_SYSTEM, hInstance, hr, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR) &lpMsgBuf, 0, NULL);
lstrcpy(m_szErrMsg, (LPTSTR)lpMsgBuf);
LocalFree( lpMsgBuf );
} }
/*转换DB_NUMERIC 为标注格式 XXXXX.XXX */ void COLEDBDatabase::ConvertNumericToChar() { memcpy((char*)&dbInt64,dbNumeric.val,sizeof(__int64)) ; memset(szNumeric,0x00,sizeof(szNumeric)) ; _i64toa(dbInt64,szNumeric,10) ; nNumericLen = strlen(szNumeric) ; if(dbNumeric.scale>0) { memmove(szNumeric+(nNumericLen-dbNumeric.scale+1),szNumeric+(nNumericLen-dbNumeric.scale),dbNumeric.scale) ; szNumeric[nNumericLen-dbNumeric.scale]='.' ; } if(dbNumeric.sign==0) { memmove(szNumeric+1,szNumeric,strlen(szNumeric)) ; szNumeric[0]='-' ; } }
/*取得每一列的值 */ void COLEDBDatabase::MyGetColumnValue() { m_CmdQuery.GetColumnInfo(&m_nColCount,&m_pColsInfo,&m_pStrBuffer) ; for(int i=0;i<m_nColCount;i++) { nColType = m_pColsInfo[i].wType ; m_CmdQuery.GetStatus(i+1,&dbStatus) ;
if(dbStatus==DBSTATUS_S_ISNULL) {/*该列为空*/ m_sFieldValue[i][0]=0x00 ; continue ; } if(nColType==129) {/*CHAR*/ strcpy(m_sFieldValue[i],(char*)m_CmdQuery.GetValue(i+1)) ; }else if(nColType==133) {/*DATE*/ memcpy((char*)&dbDate,(char*)m_CmdQuery.GetValue(i+1),sizeof(DBDATE)) ; sprintf(m_sFieldValue[i],"%d-%.2d-%.2d",dbDate.year,dbDate.month,dbDate.day) ; }else if(nColType==134) {/*TIME*/ memcpy((char*)&dbTime,(char*)m_CmdQuery.GetValue(i+1),sizeof(DBTIME)) ; sprintf(m_sFieldValue[i],"%d:%.2d:%.2d",dbTime.hour,dbTime.minute,dbTime.second) ; }else if(nColType==135) {/*TIMESTAMP */ memcpy((char*)&dbTimeStamp,(char*)m_CmdQuery.GetValue(i+1),sizeof(DBTIMESTAMP)) ; sprintf(m_sFieldValue[i],"%d-%.2d-%.2d %.2d:%.2d:%.2d",dbTimeStamp.year,dbTimeStamp.month,dbTimeStamp.day,dbTimeStamp.hour,dbTimeStamp.minute,dbTimeStamp.second) ; }else if((nColType>=2 && nColType<=3) || (nColType>=18 && nColType<=21)) {/*short LONG ULONG */ memcpy((char*)&dbLong,(char*)m_CmdQuery.GetValue(i+1),sizeof(LONG)) ; sprintf(m_sFieldValue[i],"%d",dbLong); }else if(nColType==131) {/*DB_NUMERIC */ memcpy((char*)&dbNumeric,(char*)m_CmdQuery.GetValue(i+1),sizeof(DB_NUMERIC)) ; ConvertNumericToChar() ; /*进行转换*/ strcpy(m_sFieldValue[i],szNumeric) ; }else /*空值或者未知类型 */ m_sFieldValue[i][0]=0x00 ; } } 
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