一个简单的数据库连接为什么不成功w

[kezhon]

void CAdoDlg::OnBtnQuery() 
{
	// TODO: Add your control notification handler code here
        CoInitialize(NULL);
	_ConnectionPtr pConn(__uuidof(Connection));
	_RecordsetPtr pRst(__uuidof(Recordset));

	pConn->ConnectionString="Data Source=KEZHON-PC\SQLEXPRESS;Initial Catalog=Love;Integrated Security=True";
                               //连接字符串是在vs2008中建立了一个连接，然后把连接字符串复制过来得到的
	pConn->Open("","","",adConnectUnspecified);

	pRst=pConn->Execute("select * from nets",NULL,adCmdText);
  
	while(!pRst->EOF)
	{
		((CListBox *)GetDlgItem(IDC_LIST1))->AddString(
			(_bstr_t)pRst->GetCollect("id"));
		pRst->MoveNext();
	}
	pRst->Close();
	pConn->Close();
	pRst.Release();
	pConn.Release();
	CoUninitialize();
}

编译成功，运行就出问题，大侠帮忙看看，谢谢！

[kezhon]

在连接字符串那一行有一个警告：
AdoDlg.cpp(180) : warning C4129: 'S' : unrecognized character escape sequence

[oakfire]

try catch看下出错信息

[zaodt]

PC\\SQLEXPRESS


两个\\

[kezhon]

两个也不行啊

[MBWQ]

pConn->Open("","","",adConnectUnspecified);
低级错误

[kezhon]

不太明白您的意思，新手，能不能说详细点。

[shakaqrj]

你的连接字符串...
不知道你连的是什么数据库
新建一个udl文件，配置，最后用记事本打开，里面的就是连接字符串

[kezhon]

您真是高人啊，我照你的方法已經成功了，真是太太感謝了！！

[shakaqrj]

双斜扛后抱什么错？？

[kezhon]

双斜杠后编译无错，运行的时候，一点击“查询”，就弹出对话框“Debug Error!”,问中止，重试还是忽略，点击忽略，则弹出对话框曰“Runtime Error!”

[shakaqrj]

try{
...
}catch(_com_error e){
messagebox(e.description)
}

[kezhon]

void CAdoDlg::OnBtnQuery() 
{
	// TODO: Add your control notification handler code here
    CoInitialize(NULL);
	_ConnectionPtr pConn(__uuidof(Connection));
	_RecordsetPtr pRst(__uuidof(Recordset));
    
	try
	{
	pConn->ConnectionString="Data Source=KEZHON-PC\\SQLEXPRESS;Initial Catalog=Love;Integrated Security=True";

		//"Data Source=KEZHON-PC\\SQLEXPRESS;Initial Catalog=Love;Integrated Security=True"
	pConn->Open("","","",adConnectUnspecified);

	pRst=pConn->Execute("select * from nets",NULL,adCmdText);
	}
	catch(_com_error e)
	{
        MessageBox(LPCTSTR(_bstr_t(e.Description));//编译出错的行
	}

	while(!pRst->rsEOF)
	{
		((CListBox *)GetDlgItem(IDC_LIST1))->AddString(
			(_bstr_t)pRst->GetCollect("id"));
		pRst->MoveNext();
	}
	pRst->Close();
	pConn->Close();
	pRst.Release();
	pConn.Release();
	CoUninitialize();
}

编译错误：
C:\Users\kezhon\Desktop\PropertyInDlg\Ado\AdoDlg.cpp(193) : error C2440: 'type cast' : cannot convert from '' to 'class _bstr_t'
No constructor could take the source type, or constructor overload resolution was ambiguous
C:\Users\kezhon\Desktop\PropertyInDlg\Ado\AdoDlg.cpp(193) : error C2143: syntax error : missing ')' before ';'

[shakaqrj]

MessageBox(e.Description())

[kezhon]

真抱歉，犯了个这么愚蠢的错误。
try...catch捕获的错误是“多步OLE DB操作产生错误。如果可能，请检查每个OLE DB状态值。没有工作被完成。”
这是什么意思。

[kezhon]

void CAdoDlg::OnBtnQuery()
{
// TODO: Add your control notification handler code here
CoInitialize(NULL);
_ConnectionPtr pConn(__uuidof(Connection));
_RecordsetPtr pRst(__uuidof(Recordset));


pConn->ConnectionString="Data Source=KEZHON-PC\\SQLEXPRESS;Initial Catalog=Love;Integrated Security=True";

try
{
pConn->Open("","","",adConnectUnspecified);//问题应该出在这一步......

}
catch(_com_error e)
{
MessageBox(e.Description());
}
pRst=pConn->Execute("select * from nets",NULL,adCmdText);


while(!pRst->rsEOF)
{
((CListBox *)GetDlgItem(IDC_LIST1))->AddString(
(_bstr_t)pRst->GetCollect("id"));
pRst->MoveNext();
}
pRst->Close();
pConn->Close();
pRst.Release();
pConn.Release();
CoUninitialize();
}

[kezhon]

try 
{ 
pConn->Open("","","",adConnectUnspecified);//问题应该出在这一步...... 

} 
catch(_com_error e) 
{ 
        MessageBox(e.Description()); 
} 

我把try...catch的范围缩小到pConn->Open()这一句代码时会弹出“多步OLE DB操作产生错误。如果可能，请检查每个OLE DB状态值。没有工作被完成。” 的错误提示。try...catch其他的语句则不会捕捉到异常提示。

[UltraBejing]

接分先！

[meiZiNick]

这个简单啊,网上搜一下就得到答案了.