各位大哥,我想用下面的句子打开数据库时是成功的,
_ConnectionPtr m_pConnection;
AfxOleInit();
m_pConnection.CreateInstance(__uuidof(Connection)); m_pConnection->Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\\1234.mdb","","",adModeUnknown);问题是:如果当前在D盘上没有1234.mdb文件,我想直接创建一个空的access文件,应怎么做,100分相谢。
_ConnectionPtr m_pConnection;
AfxOleInit();
m_pConnection.CreateInstance(__uuidof(Connection)); m_pConnection->Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\\1234.mdb","","",adModeUnknown);问题是:如果当前在D盘上没有1234.mdb文件,我想直接创建一个空的access文件,应怎么做,100分相谢。
#import "c:\Program Files\Common Files\system\ado\msadox.dll"
#import "c:\Program Files\Common Files\system\ado\msado15.dll" no_namespace rename("EOF", "EndOfFile")
#pragma warning (default: 4146)将上述代码加入到stdafx.h文件中,由于ado是com组件,因此使用ado之前还要初始化com环境:CoInitialize(NULL);下面是一个在access数据库中创建表的sql语句的例子:create table test
(
nametext(20) WITH COMPRESSION not null,scoredecimal(12,4) not null default 0,ID smallint not null default 0,birthday date,sex char(1),CONSTRAINT CK_CH_SEX Check(SEX in ('N','V')),CONSTRAINT PK_ID Primary Key (ID));使用ADOX::CatalogPtr来创建mdb文件:HRESULT hr = S_OK;//Set ActiveConnection of Catalog to this string
CString strcnn(_T("Provider=Microsoft.JET.OLEDB.4.0;Data source = d:\\test.mdb"));
try
{
ADOX::_CatalogPtr m_pCatalog = NULL;
hr = m_pCatalog.CreateInstance(__uuidof (ADOX::Catalog));if(FAILED(hr)) {_com_issue_error(hr); } else {
m_pCatalog->Create(_bstr_t(strcnn)); //Create MDB }
}
catch(_com_error &e)
{
// Notify the user of errors if any.
AfxMessageBox(_T(“error“));
}创建一个连接对象打开刚刚建立的mdb文件:_ConnectionPtr g_pConn;g_pConn.CreateInstance(__uuidof(Connection));g_pConn->Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\\test.mdb;",
"", "", adConnectUnspecified); 下面函数用来执行sql文件中的sql语句:// Function name : RunSqlScript
// Description: 执行SQL脚本, [email protected], 2003-09-15
// Return type: BOOL 成功返回TRUE
// Argument : LPCSTR SqlScriptFile SQL脚本文件名
// Argument : char separator SQL 分割符号, 缺省';'
// Argument : char ReSQL 注释符号, 缺省'-'
BOOL RunSqlScript(LPCSTR SqlScriptFile, char separator = ';', char Re = '-')
{
BOOL bRet = FALSE;
CFileFind finder;
CString ErrLong;
if (finder.FindFile(SqlScriptFile) == TRUE)
{
CFile fSql;
TCHAR *buffer, *pSQL, *p;
fSql.Open(SqlScriptFile,Cfile&::modeRead);
UINT nFileLength = fSql.GetLength();
buffer = (TCHAR *)malloc((nFileLength + 1) * sizeof(TCHAR));
_tcsnset(buffer, TCHAR('\0'), nFileLength + 1);UINT nBytesRead = fSql.Read(buffer,nFileLength); //把sql文件内容读入内存缓冲区
fSql.Close();p = pSQL = buffer;
BOOL bRunOK = FALSE;
BOOL bInNote = FALSE;
BOOL bSkip = FALSE;
CString strSQL;
TCHAR ch;
ErrLog = _T("");
while (p < (buffer + nFileLength)){
//判断是否是注释行
if (bInNote)
{
if (*p == TCHAR('\x0a'))
bInNote = FALSE;
}
else
{
if ((*p == Re) && (*(p+1) == Re))
{
bInNote = TRUE;
p++;
}
else
{
//判断是否是sql语句结束标志
if (*p == separator){
strSQL = _T("");
bSkip = FALSE;
while (pSQL < p)
{
if (bSkip == FALSE){
if ((*(pSQL) == Re) &&(*(pSQL+1) == Re))
{
bSkip = TRUE;
pSQL++;
}
else
{
ch = *pSQL;
strSQL = strSQL+ch;
}
}
else{
if (*pSQL = TCHAR('\x0a')){
bSkip = FALSE;
ch = TCHAR(' ');
strSQL = strSQL + ch;
}
}
pSQL++;
}
pSQL = p + 1;
ErrLog = ErrLog + _T("-- SQL Running ...\n");
ErrLog = ErrLog + strSQL;
_variant_t vRecords;m_nRecordsAffected = 0;try
{
g_pConn->CursorLocation = adUseClient;
g_pConn->Execute(_bstr_t((LPCTSTR)strSQL), &vRecords, adExecuteNoRecords);
m_nRecordsAffected = vRecords.iVal;
bRunOK = TRUE;
}
catch(_com_error &e)
{
bRunOK = FALSE;
}
if (bRunOK)
ErrLog = ErrLog + _T("\n-- Successed!\n");
else
{
ErrLog = ErrLog + _T("\n-- Failed!\n");
break;
}
}
}
}
p++;
}
free(buffer);
bRet = bRunOK;
}
return bRet;
}调用RunSqlScript创建access数据库中的表:RunSqlScript(_T("d:\\test.sql"));关闭数据库连接:g_pConn->Close();::CoUninitialize();