连接sql2008连接字符串问题？

Question

m_pConnection->ConnectionString = "Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1";这样就能连上数据库
_bstr_t strCnn("Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1");这样就连不上，为什么呢？

Answer 1

_bstr_t strCnn("Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1");
仅仅是给_bstr_t类型变量赋值了?!
http://blog.csdn.net/zyq5945/archive/2010/05/13/5586423.aspx

Answer 2

BOOL ADO_sql::InitADO(WCHAR szSqlCnn[])
{
//初始化OLE/COM环境
CoInitialize(NULL);
try
{
m_pConnection.CreateInstance(__uuidof(_Connection));
                
//m_pConnection->ConnectionString = "Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1";//这种方式能连上
_bstr_t strCnn("Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1");//但定义个_bstr_t变量，使用这个变量值就连不上了

m_pConnection->Open(strCnn,"","",NULL);
}
catch(_com_error &e)
{
return FALSE;
}

Answer 3

BOOL ADO_sql::InitADO(WCHAR szSqlCnn[])
{
//初始化OLE/COM环境
CoInitialize(NULL);
try
{
m_pConnection.CreateInstance(__uuidof(_Connection)); //m_pConnection->ConnectionString = "Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1";
//m_pConnection->Open("","","",NULL);
//上面这种方式能连接成功
_bstr_t strCnn("Provider=SQLOLEDB.1;Password=farmers;Persist Security Info=True;User ID=sa;Initial Catalog=Dining;Data Source=127.0.0.1");
m_pConnection->Open(strCnn,"","",NULL);
//这种方式连接失败
}
catch(_com_error &e)
{
return FALSE;
} return TRUE;
}

Answer 4

我试了一下俩个都可以正常打开
HRESULT hr = S_OK;
_ConnectionPtr m_pCon = NULL;
m_pCon.CreateInstance(__uuidof(Connection));
m_pCon->ConnectionString = "Provider=SQLOLEDB.1;Server=127.0.0.1;User ID=sa;Password=sa@2008;Persist Security Info=false;Initial Catalog=tempTable;";
hr = m_pCon->Open("","","",NULL);
if (m_pCon->GetState())
{
m_pCon->Close();
}
if (!m_pCon->GetState())
{
AfxMessageBox("关闭成功");
}

m_pCon.CreateInstance(__uuidof(Connection));
_bstr_t strConn("Provider=SQLOLEDB.1;Server=127.0.0.1;Persist Security Info=True;Initial Catalog=tempTable;User ID=sa;Password=sa@2008;");
hr = m_pCon->Open(_bstr_t(strConn), "", "", NULL);
long liStatus = m_pCon->GetState();
if (m_pCon->GetState())
{
AfxMessageBox("打开成功");
} if (hr == S_OK)
{
return true;
}

Answer 5

贴上自己 VC 连接 MSSQLServer2008的连接代码： ::CoInitialize(NULL);
try
{
m_pConnection.CreateInstance("ADODB.Connection");
_bstr_t strConnect="Provider=SQLNCLI10.1;Integrated Security=SSPI;Persist Security Info=False;User ID='';Initial Catalog=UserMan;Data Source=SYX-PC\\SQLEXPRESS;Initial File Name='';Server SPN=''";
MessageBox(NULL, strConnect, "" , 0);
m_pConnection->Open(strConnect,"","",adModeUnknown);
}
catch(_com_error e)
{
AfxMessageBox(e.Error());
}本人的方法是先添加个 ADO DATA CONTROL用这个连接上数据库在复制它自动生成的连接字符串！

Answer 6

将return FALSE;改成AfxMessageBox(e.Description());
看看捕获的错误是什么～