请教数据类型转换的问题（SQL Server和C++）

[ranman]

我在_RecordsetPtr的Open()函数里使用如下的联机字符串：
"SELECT * FROM workID WHERE word_id='"+m_strName+"' AND passw='"+m_strPass+"'"但是编译的时候出现如下的错误：
cannot convert parameter 1 from 'class CString' to 'const class _variant_t &'
请问我该怎么做？

[丁淇石头]

试试这个：
char buf[100];
HRESULT hr;
try
{
hr=m_pConnect.CreateInstance("ADODB.Connection");
if(SUCCEEDED(hr))
{
sprintf(buf,"SELECT * FROM workID WHERE word_id='%s' AND passw='%s'"， m_strName, m_strPass);
hr = m_pConnect->Open(buf, "", "", adModeUnknown);
}
}
catch(_com_error e)
{
AfxMessageBox(e.ErrorMessage());
return FALSE;
}

[丁淇石头]

试试这个：
char buf[100];
HRESULT hr;
try
{
hr=m_pConnect.CreateInstance("ADODB.Connection");
if(SUCCEEDED(hr))
{
//先将SQL组装好
sprintf(buf,"SELECT * FROM workID WHERE word_id='%s' AND passw='%s'"， m_strName, m_strPass);
hr = m_pConnect->Open(buf, "", "", adModeUnknown);
}
}
catch(_com_error e)
{
AfxMessageBox(e.ErrorMessage());
return FALSE;
}

[karlson0211]

我记得好象是：_variant_t strQueary;
strQueary="SELECT * FROM workID WHERE word_id='"+m_strName+"' AND passw='"+m_strPass+"'"再试试？

[yanzai8848]

CString strSQL;
strSQL = "SELECT * FROM workID WHERE word_id='"
+ m_strName
+ "' AND passw='"
+ m_strPass
+ "'";

在Open()函数的SQL语句参数中使用

strSQL.LockBuffer();

在Open()之后加上

strSQL.UnLockBuffer();

[commandconque]

你干脆写成：
->Open( _variant_t("select * from ....");
_variant_t((IDispatch *)m_connection,TRUE),
...,
...,
adCmdText);